My husband and I have been together 7 years. Married for 5. We have a son together and custody of his 9 year old daughter from a previous relationship. My husband dated this girl when they were like 14. She is his sister’s bestfriend and has always been around for everything. About a year ago, one of his brother’s got drunk and she had *** with him. I just found out my husband got drunk this weekend, ran into her and his sister in a bar and low and behold he slept with her. I’m so ****** right now. She is just plain nasty. She’s been with every guy she meets. Her last relationship was with a drug head. Who knows what diseases she could have. Now my husband is “sorry” and wants me to forgive him. I just lost my job, which was making me miserable anyway. I’ve been depressed for a few years now and this doesn’t help any. I look at my son and just want to cry because deep down I know the right thing to do is leave, but how?