I could have written that myself... we are exactly in the same place. I knew exactly what I was getting into when I started a relationship with my XABF. Except, he was only drinking the first week of our relationship. He's a 20 year alcoholic who is now in his seventh month of sobriety, which we didn't make it through. He may not be drinking... but the other stuff (manipulation, shady behavior, etc.) is all still there.
I try to think about it the way your friend advised you, but it's not easy sometimes. I still miss him, I still love him, but I am also so very angry. At him and myself.
I know it will get better eventually, if I keep doing the right thing and making good decisions. But right now? Right now it just sucks.