What do I do, and why is she acting this way?

A very good friend of mine was showing signs of drug abuse(Hydrocodone) very severe signs of addiction. I went to her parents, we planned an intervention and she went to rehab. She is now back, and is completely clean. But she is leaving her husband, and her two little girls and is getting an apartment. She doesn’t even seem to care. He is a GREATguy and an even better dad. He is truly outstanding! and she is walking away. I think she met someone in rehab and is going to mess up her life!!! What can I do? I feel like its my fault because I told in the first place! what do I do?

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