I have been cheating on my husband and I hate myself for it.
Ouch. Why did you cheat?
After I came back from a party and found out that my husband had cheated on me, I fell into a deep depression and I couldn't focus on my work.
We all do actions that we regret doing later, it's part of the human experience. While cheating shouldn't be done, you shouldn't continually hate and blame yourself, especially since there were so many other problems occurring in your marriage with your husband. You should talk with a couples counselor in order to help resolve the cheating and other serious issues that are happening in your marriage.
I don't want to talk it out and solve the problem. I want to ignore the problems and try to keep them inside.
Well if you don't deal with this problem you might internalize your hate even more. People can do crazy things when they feel hurt and you should not beat yourself up for it.