Help with my ex!

I was dating my ex for a year. We had a lot of ups and downs but we were so good. He has a daughter and didn’t introduce me for months on end because it was his first time doing that since his divorce. His daughter and I hit it off and she was amazing. We ended up taking a break towards the end of December and when we started talking again 2 weeks later, he mentioned his daughter thought I was mean to her. I never was and he knew that too, but his daughter obviously comes first and that was it. We’ve been talking here and there since the breakup a month ago and agreed to be friends. I went to Vegas this past weekend and he was texting me constantly. He was flirting with me and asking for pics which I sent which was dumb on my part. This continued for 5 days. Today I called him asking if I could get something from him and he apologized for texting me like that and said he wants to just be friends for now. I heard through his cousins gf today that she thinks he’s talking to another girl and has been on dates with her. I was instantly mad because why text me flirtatiously when that might be happening. I called him to confront him about another suspicion I had, that way I didn’t have to mention where I heard it from. He told me he doesn’t have time to date let alone have a girlfriend (he casually told me this earlier) and that he promises me that he isn’t talking to anyone. He told me to trust him like I always have (he’s never broken my trust). I ended up going to his house later to pick something up and I mentioned it again briefly. I told him I deserve that respect to be told the truth and he agreed. I told him I’d much rather know the truth than not and he agreed as well and reassured me again. I also told him that if he did that that’s so low and I’d genuinely hate that person, and he agreed that I should be mad if that did happen. We hugged super quickly. He told me I looked nice and I left. My anxiety is so high right now as I don’t know what to think. I want to trust him and he’s always been man enough to respect me and tell me the truth. However, my anxiety is once again getting the best of me and I just wish I could verify that he’s telling the truth.