I just need to get this out because I'm upset, angry and scared.
I was seeing someone in January. My ex DP found out and chastised me for "moving on too quick", "cheapening our relationship" and "it's a rebound" (I left him in September after 7 years, including abuse to me and our son). One of his main issues was he did not want me to introduce a partner to our child (5) until 4-6 months, a rule he stipulated himself. I agreed to this, and we both agreed that should this time roll round, we would discuss with each other to ensure that our son's best interests were considered.
Shortly after this, ex DP met someone online. He told me when they'd met (early Feb). He said he wanted to date as he realised me doing it didn't hurt and he was ready, all fine. Again, we discussed the 4-6 month rule in place just to reiterate - this was drawn up over email and agreed to both in email and SMS.
In late Feb, our relationship became hostile when I discovered and notified ex DP that he had cheated on me in Jan 2020. I made the mistake in letting him know I knew, which is on me, but I was emotional and upset. From that moment on, things have been incredibly hostile - he took 2 weeks off work due to "mental stress" which culminated in him seeking my advice and support when he was going to break up with his new girlfriend, as well as anxiety over the Ukraine situation. I offered my support (wrongly) and spent a while listening to him discuss our past, his current relationship, and his general anxieties.
Two days later, he went to his new girlfriends (exactly a month ago) to split up. For whatever reason, they didn't. When I rang him the next day to see if he was OK as I was worried about his mental health, he told me to stay out of his life and blocked me. The day before, he said he wanted us to be "friends" and that he always "cared about me and wanted me in his life". I was confused and upset. I then got an email which advised me that he wanted to introduce his girlfriend to our child after 3 months, not 4-6. Given they had just nearly split up, I asked for 4-6 to remain in place and he eventually agreed, and also requested that I "must stick to this too".
Fast forward to this weekend. We have had very minimal contact between now and then. My son was dropped off yesterday evening with no Mother's Day card (to be expected) and told me about the wonderful weekend he had meeting Daddy's girlfriend who bought him a present. At no point did ex DP discuss with me that this was happening, furthermore, did not advise me of this when recapping his weekend.
I sent a SMS to him advising him that I was aware of this, that he had broken the agreement in place, that I was disappointed at the disrespect and that I would have to think about further steps as it appeared he feels unable to co-parent amicably.
I received a hostile, accusatory, deceptive SMS in return which essentially justified his decision and claimed he and girlfriend had been together longer, he only agreed to 4-6 months (despite it being his initial request) because I am "controlling" and that he himself has concerns about my parenting and will be considering next steps as he does not think I prioritise my son. He called me hysterical, emotionally manipulative and a liar and that I have withheld access to my son to him - he didn't have access twice because of a) refusing to pick our son up from my Mum and b) verbally assaulting me in front of our child and causing him emotional distress. At no other point has there been an issue with access.
I am at a loss. I have literally done everything he has asked me to do, agreed to the rules written up, minimal contact, etc. Initially I was emotional when he came to my house and I was worried for him, so I may have made more phone calls/texts to him than necessary, but since then I have done nothing.
In contrast, he has continually overstepped boundaries, including this weekend. There is no court order in place (he doesn't want one) and all agreements have been between the two of us.