Hello and welcome.
Let me ask you something, if a close friend came and told you this story and asked for your advise, what would you say? Often times I have found we will expect so much when telling others what we know to be true (and are correct), but when we have to apply those same things to our own lives we cannot or will not.
A life with an addict is one that is full of pain and misery many many times. She needs to focus on being alone and being clean. You need to focus on why you make this sort of choice in a person to begin with, and accept these things that are unacceptable. Being an addict is not an excuse to be a liar or to be unfaithful. You deserve more.