Blaming his horrible actions on his mental illness

Ive been with my boyfriend for two years. He’s a 41 year old cop with PTSD and a TBI, three children, all by different women. Divorced twice. I’m a 31 year old attorney with no baggage. Up until this April our relationship seemed perfect. He was the most caring partner I’ve ever had. And honestly the only one I’ve ever felt was a real partner. I had always looked for.someome who understood by work and he more than understood it. We were ride or die, especially when it came to our professional lives.

In April I learned he had been cheating on me our whole relationship. When he finally ended it with her because we were about to move in together she posted everything on Facebook. I found it in me to forgive him because monogamy to me isn’t everything. Not long after though it was like he emotionally imploded. Became paranoid that in the future I’ll hold it against him and leave him and became obsessed with a man I saw prior to him but that we still work closely with. He ended it with me and I was a mess. After about a month he missed me and came back.

For a month and a half hour relationship seemed better than ever. He even told me he WAS going to marry me, which before he said he wasn’t sure whether he would ever want to again. Then I got a call from the other woman again. Apparently she convinced him to talk to her and he cheated again. He then tried to tell her it was a mistake and end it again and that’s why she contacted me.

I again stayed and was over it after a day. But I did ask if he wanted an open relationship because if he keeps doing this it’d only be fair for me to as well since when we were apart plenty of men tried to date me. A few days later he told me that me saying that rly bothered him and asked about who these other men were and how they contacted me. I told him but also said I haven’t spoken to any of them since we got back together. A few days later he again imploded, said we’re over and to go find one of my younger and better options.

Two hours after telling me this he continued to call me for the next three days like normal, like he never said any of that. I finally asked if we could hangout and he told me he wants to spend some days apart to see how it feels. I lost it and told him to stop calling and texting me.

That same night he called me to recommend I cancel our upcoming vacation. I again lost it and sent him paragraphs about how I do nothing but try to make him happy, giving him examples and how he’s going to miss me when everything starts reminding him of me. I also told him multiple times to leave me alone until he gets his head out of his ass. Unfortunately, I ended the slew of texts that it was upsetting to me he can’t even care enough to respond.

Unfortunately, I feel in my gut he’s going to come back again and I’ll go back. I blame these issues on his mental health and tell myself I can’t blame him for it. So I feel like I’m dying in the meantime and don’t know what to do. Before everything really.blww up he agreed to couples counseling and maybe even meds for once. I don’t know what to do.