Heart is broken, I need some serious advice.

Bf of 7 1/2 years cheated on me 9 month ago, had a baby on me with a 22 year old girl, and he is 41 years old move out my house and moved in her apartment with her. I'm still hurting from this, l lost interest in everything, sex, going out, at times I don't even go out side, my daughter tried to get me to go out but I can't. Please help ty