She is married, met through your friend and decided to go with you? no no no none of this is right. She has interest in far too many places and just sounds like she is looking for an escape... and the drugs support that idea.
At the beginning of the post I supported you, I met my girlfriend in a similar manner, and we've been together years now. It was a double date I got dragged into last min, and my date was weird... but my friend's date liked me and made an excuse to keep in contact then made the first move. She was genuine though, and very managomous.
This just seems like she's a user.
Ever hear the expression 'women are like monkeys swing from branch to branch when it comes to changing men. They need to make sure they have a firm grip on the next branch before they can let go of the other!' Of course this is not the majority women, but still is common enough.