At first the couple lived happily together in Mares' mobile home with her two youngest children Uriah and Joseph – keeping their relationship a secret from the world.
Mares' youngest son even began calling Peterson 'dad'.
But police soon found out about the clandestine affair during a call over a row between the family and some neighbors.
The couple was charged with incest – a fourth-degree felony in New Mexico - following the February 25th incident.
They were arraigned and appeared jointly in court in April – but were held in custody for breaching their no-contact order.
They were released on $5,000 bond and now face a trial by jury in September.
Currently Mares is not allowed to see any of her children or have any contact at all with Peterson.Yet she maintains that is has all been worth it.
'It is every bit worth it,' she said. 'If they lock me up for love then they lock me up. There is no way anybody could pull us apart, and I really do love him.
'It hurts he is far away. It hurts really bad. I wish I could see him, talk to him, but I can't risk it.'
Peterson said he started falling love with his mom about a week after meeting her - but claims as he grew up with an adopted parents he never really saw Mares as his mother.
'I never had anyone cook me meals or give me anything,' he said. 'I never got anything my entire life and she went out of her way to make me happy and after about a week or so I started having feelings for her and I guess I fell in love.
'It went beyond a mother-son relationship I never really viewed her as my mom. In certain aspects I do but mostly I don't.
'I never thought I was crazy for having these feelings because I didn't see her as my mom, it was more like going to a club and meeting a random person. It didn't feel wrong, it felt normal.'
Peterson claims it was him who made the first move not his mom.
He recalls: 'We were hanging out just talking and I looked at her and she looked at me and I kissed her.
'It was a real kiss it had feelings behind it, there was a spark that ever since then it just stayed.
'Honestly I never thought we would get into trouble for our relationship. We were both consenting adults - when it comes down to it.
'She's adult I'm adult I can make my own decisions. I never thought it would blow up into something like this.'
Mares also said that it didn't feel strange or wrong when the couple began their sexual relationship - but admits that it probably wouldn't have happened if she had raised Peterson.
'The first time we were physical ended up holding hands and then we ended up kissing and the kissing led to other things,' she said. 'I felt comfortable with him and we fell even more deeply in love.
'If he had been with me all his life I don't think anything would have happened between us.'
As well as legal trouble, the couple has met opposition from friends, neighbors, family members and the wider community.
Mares has been attacked outside her home and subjected to death threats.
She said: 'I've been having a lot of trouble from the people in Clovis. They call me incest.
Mares says other moms she knows don't understand what she's going through but says her kids have said they will love her no matter what.
But with a torn look on her face, she added: 'But if I had to choose between my son and all my other kids I'd chose him.'
Peterson added: 'My dad walked out on me because of it.
'There's a lot of negative comments I read on Facebook and things - people say it's disgusting, it's gross, she's your mom but it doesn't hurt me or affect me at all.
'If they were in my situation or if they were to find out that somebody they loved was actually related to them then they'd be saying the exact opposite.'
Peterson admits that sometimes he wonders if he should have done things differently - if only to spare his family the pain.
But he said that even if the judge offered to spare him jail if he stopped all contact with his mother, he would refuse.
And he has vowed to wait for Mares if she is jailed and he isn't.
'Sometimes the easy way isn't the best way,' he said. 'Sometimes we have to make that life decision that's going to change and affect everything but when it comes down to it, it's worth it.
'I will wait for her if she gets a jail sentence and I don't. For me it's not about patience it's about commitment.
'If I'm committed to something I follow it through that's the kind of person I am.
'If I love her enough and I'm crazy enough to stay in Clovis for her and crazy enough to face all the courts for her then waiting a bit of time to have the rest of my life being happy then I'm willing to do that.'
Daily Mail Online interviewed the couple separately to ensure they did not breach their court order.
As a sign of his love and commitment, Peterson left a rose for Mares on the bench at the park in Clovis where the couple first expressed their love for each other.
He said: 'She's never had anyone give her a rose. If I could I'd give her everything she wants. I miss talking to her and seeing her. There's not a day that goes by that I don't think about her.
'If I could speak to her now I would say to her: "I love you and I miss you and I can't wait to see you again."'
Despite the immense opposition to the couple's relationship, Mares and Peterson do have supporters in the community - including Dayton Chavez, Mares' ex and father to two of her sons Moses, nine, and Joseph, 12.
He said: 'I've told them I still love you guys either way. I support them.
'I would like to see the government get out of their business and let them live a normal life - let them live how they want to live.
'It would be different if it was a domestic violence situation but it's not.
'My point of view is they need to be allowed to live just how they are that's what America is built on.'
The couple - who both have roots with Native American Apache tribes - is also being supported by Cristina Shy who runs
www.lilysgardener.com, a support and advocacy website for related couples, also known as consanguinamorous people.
Cristina, who is involved in an illegal relationship with her half brother in Minnesota, said: 'Our whole community is watching this case and looking for updates.
'It needs to be brought to the attention of everybody in the country and people need to start thinking differently.
'It was the same with gay people just a few years ago and now they can get married they are accepted.
'Well why not consanguinamorous people like us? We are all adults. We are not pedophiles, there's no domestic issue we are in love, we want to be together but we are related. That shouldn't be a deciding factor.'
Cristina is hoping to raise enough money to get a high profile attorney to defend the case and says the couple is willing to fight all the way to the US Supreme Court.
'This case could set precedent and change laws throughout the United States,' she said.
But Prosecutor Andrea Reeb, District Attorney for the Ninth Judicial District in New Mexico, doesn't agree.
She says incest is against the law and carries a maximum 18 month jail term and/or a $5,000 fine.
Speaking to Daily Mail Online from her office in Clovis, Reeb concedes there is a chance Peterson could be spared jail because of his age - but she's doubtful Mares will be treated as leniently.
She said: 'The law states that if you are related as they are - mother and son - you cannot have any type of sexual intimate relationship. It's a fourth-degree felony. It's the law so our office is bound to uphold the law so we are pursuing it.'
Reeb said that in her 20-year career as a prosecutor she has only handled a few incest cases.
She added: 'This case is going to be difficult only in the sense that some people think that Caleb is a victim and not a defendant.
'I have not got any feedback from the community or from anybody else believing that Monica Mares, the mother, that anybody has any sympathy towards her whatsoever.
'Both have acknowledged they knew it was wrong, they are both consenting adults so they are considered co-defendants.
'It's only a fourth-degree felony so it's the lowest level of felony in New Mexico.'
She added that if the couple reunited after their sentences - and law enforcement found out - they would be held accountable.
For Peterson, he is willing to wait for his mom if she's jailed, and despite the risk of further prosecution he still sees a happy future for the unconventional couple.
'In two years time I can see us living together happily living our lives,' he said. 'True love can do anything.
'This whole case is about whether I have the right to love somebody and I sure as hell have the right to love Monica.
'You can't tell me who to love, who not to love.'
https://www.gofundme.com/2dqp4rvj
oly: