fear of getting hurt/dying alone

I keep imagining horrible relationship-related things happening to me. One vision I always have is about an ex-boyfriend(who doesnt exist)who is trying to make my life terrible by waving his new slutty girlfriend in my face and saying mean things. Basically mentally abusing me.

I also have this voice in my head that belongs to another abusive boyfriend(who also doesnt exist) who keeps telling me that i cant leave him because no one wants me but him and that the whole world hates me. I've never even HAD a boyfriend but I cry myself to sleep most nights because I'm afraid all this will really happen to me.

I also even start to believe that no one does want me and that I'll die alone with no kids (one of my biggest fears)and sometimes I begin to think that if I change myself,none of this will ever happen. I even question my pledge to save myself till marriage because I'm afraid no one will want me.

I just wanted to know if there was a name for this phobia and how to cure it.Thanks:)