Guy I’m dating admitted he cheated in his last relationship

28f and 29m.

On our third date the conversation of cheating came up. He told me he cheated on his ex girlfriend. Pretty much they were dating for like 3 years already he was doing long distance at the time and was stupid and in college ( so early 20s? ) and that he felt bad about it and would never do something like that again/ I guess there was problems in the relationship already. They worked things out and dated for another 2 years and then things ended so I’m assuming he told her when it happened. They broke up like 3-4 years ago and he hadn’t been in a serious relationship since. On one of our other dates he told me went to therapy but never told me what for. Part of me wonders if this was something he worked through in therapy I’m not sure.

I’d like to think people can change and he was young and he seems really sweet but I can’t help but feel a bit nervous because that’s kind of a huge thing. Once a cheater always a cheater? Or just someone being young and dumb in their early 20s? I’ve done stuff at that age that I’m not proud of either but I also have never cheated either so I just don’t really understand it.