Im sorry for all of your losses...

I don't know what to tell you. It doesn't sound like OCD to me... I think it may be part of the bipolarity. my sister is bipolar and there is a part of the brain that is affected which basically impairs the "stop your current way of thinking and try somethnig new" part of the brain. It sounds like this could be easily mixed up with OCD. I think the first thing to do is to search around for a real therapist... one that specializes in bipolarity, and other mental disorders (OCD, etc)... they can assist with medication and talk therapy as well as assist you in trying to deal with all of these emotions that you have about this one girl...