IMO, Definitely an addiction. The feelings are strong in the beginning. But, I believe, after a while the OP cannot bring relief to their crisis. When with the OP, they like how that person makes them feel about themselves. Ityactually is how THEY feel about themselves. The new person in their life only sees the pretty stuff. After awhile, it changes.

Being with the OP will not fix them. That is when they realize how screwed up they are.