Your marriage may or may not work out. But this guy is not the answer.
If you can find a good counsellor to work on yourself, and make you happy for you, then you can work out if your marriage is worth staying in. But this guy is a player, a fuckboy and is worth none of your time or energy.
I felt very lost after having my 3rd baby and when I went back to work it felt like that was my real life, where people listened to me and respected my opinion, compared to home where I had three under 6 and a husband who worked long hours, and I just wanted to fade away into my work life. Had I had someone like this hanging around it could have ended very differently, but a course of anti depressants and some counselling and the kids growing up a bit shook me back to me, if that makes sense.
I'm now at the stage where my kids don't need me so much any more, in secondary school etc and I'm going through the same thing again, not really sure who I am after 15 years of small child raising. I'm back in counselling again to work through it.
Please just block him everywhere personal, ice Queen him at work and work on yourself.