My first boyfriend was a sex addict and alcoholic. It ended because he was always cheating and lying to me. 

My second boyfriend, which is the only man I've been in love with, had Bipolar II and died by suicide. I don't have anything bad to say about him, but our relationship was always so dramatic on both parts. Borderline + Bipolar= Explosive combination. 

The guy I'm dating now, is a recovering drug addict and a diagnosed Cluster B, PD. From what I read on his psychiatrist's report he has many narcissistic-histrionic traits but does not meet the full criteria to be categorized on one of them.

My theory is, that deep down I'm attracted to dramatic and unpredictable people because otherwise I get bored. The second reason, is that I can be very caring and mother-like, so I always find people who are struggling not in a predator sense of "let's exploit his vulnerabilities" but in a way of feeling loved and needed by trying to help them in their conditions. 
Obviously that always leads to frustration because you can't save anyone from their own demons. If it was that easy... 
You can help and try your best, and that's still not enough. The help that some people need is beyond our capabilities or wishes, that's because it's called illness.That's the biggest lesson I've learned from my partner's suicide. 

If you find reflected on the title: Why do you think you are attracted to unstable people?