Me (27m) and my EX (27F) have been legally separated for about 6 months now. Our split was mutual and we agreed that we would split time with the kids 50/50 and we would Co-parent to the best of our abilities.

Well not long after the separation she began dating a new guy, which didnt bother me at all, but after just a couple of months of dating she began talking about bringing him around the children. Which I was very hesitant about just because I feel a little weird about my children already being exposed to new people. Well I managed to stave it off until they were together for about 4 months. She told me he would only be brought around as a friend at first and he'd only be around about once a week. So I hesitantly agreed realizing that it's just something that has to happen at some point and I should get used to it.

The problems didnt take very long to start up though after the very first time he came around he was there the very next staying until late in the evening and even being left alone with my oldest son (6) for about 20 minutes. Then after that she was calling me at work nearly everyday that she had the kids "asking" me if it was okay if he came around for one thing or another, including the kids baseball games then getting upset when I told her that I prefer he didn't, then having him come around anyway, lying to me about rather or not he did.

This week was the worst case though. She asked if he could come along with them on a 4 day vacation out of state, that I couldn't go on because of work. I said that I'd prefer he didnt because I don't want him spending the night with them. Then she asked for a compromise that he only comes up for 2 nights and i said how about only for the last day so he can still go to the zoo with them but he didnt have to stay the night. She agreed and we moved on. Then one day on vacation my oldest son was playing on her phone and sent me a snap chat of her new boyfriend on vacation with them. Which made me upset, for obvious reasons. When they came home and I got my kids I asked my son all about it and come to find out that he was there for 2 days and slept in the same bed as my ex and my two young boys (6) and (2).

I feel really helpless about the whole situation. We were supposed to co-parent and although I do get them 3-4 days a week she doesnt actually co-parent. She makes every major decision without consulting or she will consult me and when I give her an answer she doesnt like she just lies to me and does the opposite. She's bringing her new bf around the kids way more than I'm comfortable with then playing it off like I'm the bad guy or I'm crazy because I dont like it. I dont really know what to do, but I do know I dont want some strange man sleeping in the same bed as my small children.