This therapist is acting extremly unprofessionally in trying to guilt you into returning.
Obviously I don't know you, and your MH may be worse than it at first appears to all us internet sprites but if the therapist had genuine professional concern about you not wanting to see her any more, she should still not be ringing you up and pestering you, she should refer you to someone else.
It's OK to change therapists if you encounter one who doesn't fit with you. They're only people, after all, and different patients need different things.
Mind you, something I would advise you: forget about romance and dating for the moment. If you have a history of abusive relationships, then there is something about yourself you need to change before you date again: building your self-esteem, strengthening yourself, examining your past experiences. Because, unfortunately, a vulnerable unhappy woman who has been abused in the past is both off-putting to nice men (ie a nice man who doesn't know you well is likely to decide, not unreasonably, that you have problems he can't fully cope with and he'd rather move on) - and a magnet to abusers. Abusers scent vulnerability and move in on it. YOu need a good year of taking care of yourself (and DC, if you have them) without worrying about men, sex and couplehood. Best of luck.