How can I forgive husbands meth addiction & affairs?

I just found out my husband has been hiding a meth addiction and he also had several affairs. I am heartbroken. I am so sick to my stomach that I just don’t know what to do. He is going to a 30-day rehab program to get help for the drugs but that doesn’t change the pain I’m feeling over the affairs. He and his family and my family all say he cheated because of his addiction to meth. Is there any truth to that. I just need some unbiased opinions.
We dated for 5 years before we got married and he cheated and did meth then. He finally quit sometime before we got married and promised to never do it again. I know he needs help and i’m trying to be supportive but I’m holding all this pain in because I feel like no one is there for me. I’m afraid that after rehab he has to go to meetings everyweek etc. but statistics show he will probably relapse again and I just can’t keep going through this. He only admitted to it cause he got caught.
Thank you all so much for your replies. It helps so much to hear all of your advice. You are all helping me to not feel like I’m in this all alone.

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