Falling Apart

So I’ve been with my husband for a 11 years married for 6. Recently I found out he had sex with an ex the beginning of our relationship... He always had a problem with porn and talking to other women behind my back this has been for years during our marriage .. And now it’s worse I found out he’s been on websites with escorts and I’m just so fed up to the point I literally cheated on him for the 1st time and I feel so terrible about it I did it thinking it would make me feel better knowing it wouldn’t i just didn’t understand how could u hurt someone that u chose to live it life with forever our marriage just hasn’t been good for so long but he dose not wanna leave I just don’t get I’m happy and he has to be as well to those things so I just don’t knw what to do I Know I want to leave but I just need to figure one the steps 1st I made it clear to him that I’m just not in this anymore and o can’t so this living u happy hoping change would come would come that never did and now I’m no better then him