A lot of backstory here and I'm fully prepared for negative responses because I'm in the wrong. But I just don't know what to do, and need some other perspectives.
My partner and I have never had a perfect relationship. The first 5/6 years he was unfaithful to me a lot of times, in many different ways. He brought a girl to our flat and slept with her. He formed an emotional relationship with another, telling her that if I wasn't in the picture then he'd be with her. I loved him so much and wanted to be with him at all costs, so I let it all slide and forgave him each time. We now have two kids and he's been faithful to me since the first was born. He's a SAHD and is a great parent to then.
Last year I was in a deep depression. I didn't realise it until I came out of it this year. I felt numb, like I had no emotion anymore. I raised this with him and he told me he didn't believe me - his regular response when I've told him about mental health issues. Our relationship was on the rocks. He had begun to resent me, called me useless, said I was an absent parent. I'm the breadwinner for the family so obviously have to work, but I work in marketing so occasionally my job follows me home. I was having trouble looking after myself (overeating and personal hygiene). I started to think about leaving.
Here's where I went badly wrong. I started inappropriately texting a colleague. It didn't happen out of nowhere - he'd been a friend for years and it felt nice to speak to someone who didn't view me as incompetent and useless. It got out of hand but nothing physical ever happened. It was an emotional affair. It lasted about three weeks.
My partner found out and the last six months have been hell. We've lived the same cycle over and over again. We want to make it work and fix our relationship. We have a positive week or so where we're both clearly trying to make things better. Then he perceives that I haven't paid him enough attention, or maybe I said something to upset him, or maybe I just had a busy day at work and wasn't around as much. He gets angry, gives me the cold shoulder for days as a result, and then we have a huge blowout argument (he has become violent during these arguments, he smashed our TV and broke a dining room chair) and when the dust settles we attempt to try again.
He wants sex a lot. He says that's the way he feels closest to me, but I'm on a contraceptive pill that has basically stripped away my sex drive entirely. We have argued about this a lot and I have felt pressured more than once. If I don't have sex with him for a few days he gets upset. He always needs me to dress up in lingerie and do my makeup, it can't just be the regular sex of a couple who have been together for 12 years.
I know that I have hurt him deeply. I have expressed regret and remorse many times over, but he wants me to carry on apologising endlessly, whereas I think we should be trying to move forward with our lives. He's constantly trying to pick apart what happened, he reads the chat logs between mine and my colleague late into the night and then confronts me about minor details. He's never happy with my answers, calls me a liar. He's convinced something more happened. It never did.
He tells me that I'm not enough, that I'm not doing enough for him, but when I ask him to elaborate, he can't quite explain what that means or what he expects. He's expecting me to fix the hurt he feels but, as someone who has been cheated on, that doesn't come from the other person, it comes from within.
I have suggested that we separate but he won't go. He sometimes says that he'll take the kids (with no income and nowhere to live I'm not sure how he plans to execute this). I have suggested that we stay together 'for the kids', take the pressure off ourselves trying to 'fix' everything and then see what happens to our relationship when we're just co-parenting. I've stopped suggesting we try again because we'll end up in the cycle above where a tiny misstep from me results in days of cold silence and then a huge argument.
I would love to confide in friends or family about this but since all this happened I've been very isolated and alone, hence me now turning to an anonymous forum. I know I'm in the wrong here but I want to put it right and I just don't know how. I want to do right by my children, who adore their father but are now part of an increasingly unstable household. Any advice (or flames, if you feel like it) would be appreciated.