He called and emailed but said he never went through with it. I stayed with him. Was that a mistake? I don't know what do. I'm worried! I don't want to stay with someone if they will leave me for a gay or TS later on in the relationship. I couldn't handle the mental damages from that. Please some advise?

Looks like he's cheating or seriously thinking about doing it. Just because he says he didn't follow through doesn't mean he isn't lying.

You have to decide if you want to stay with a cheater or not.

You need to talk to him and let him know that his behavior will not be tolerated. The fact that he probably hasn't cheated yet is a red flag that you need to have a serious talk about the two of you.