Finally decided to leave

I was in a relationship of 3 years. Things were great until August where he starts cheating and acting different. I tried to work last it with him but than 2 other girls poped up that he always was talking too. He said it isn't cheating because he didn't fuck anyone. He hung out with the females a few times etc. yesterday I finally put my foot done and left! I blocked him on everything and I
Blocked his number. I'm good about cutting people off when I need too! But my heart is broken and dont know how to deal with it. I haven't had a broken heart in years and i all I want to do is cry. I was nothing but an amazing women to this guy but he was constantly lying and making me feel like shit.  How do you deal with leaving someone you love because they treat you like shit ? How did you deal with a broken heart ?