It sounds like he wasn't fully committed in the first place. Kissing other people, lying about being married (what the hell), shifting the blame and not taking responsibility.
Usually I am all for saving a marriage, I take those vows vows very seriously, however, all this in the first year!

I would call irreconcilable differences on this one. I don't hear where the love was even before all this happened.
I am sorry for your situation, and wish you all the best whatever you decide. Please be kind to yourself.