Probably a stupid question but relationship advice

I'm really just not sure what to do in this situation. My male best friend is my ex-boyfriend. We still communicate the same way we did when we were together, still hook up on occasion. We talk everyday but I'm really not about having an "almost relationship." Anyway, he said he didn't want to date because of personal issues, which I respect and understand, but now he's going out on dates with other women, while telling me almost hooking up with someone else felt like cheating on me. I don't know.  I kinda feel betrayed. I'm good enough to sext and hook up with and date at one point, but now I'm not? This has happened to me twice now and I'm just not sure what to do or how to avoid this happening ever again.