I don't think you can get there from this vantage point; all relationships have to end at some point; death, moving house, changing jobs, divorce, growing up and leaving one's childhood family, getting married being an end to being a dependent child, etc. You might want to work on getting into more relationships, maybe try group therapy, and get the hang of the ebb and flow of relationships so you are better able to maintain yourself before starting a therapy relationship.

Therapy isn't magic, does not cure you in and of itself, the therapist does not cure you at all, you do all the work, they just help guide you as you do the work with yourself. I would try a relationship with a social worker, just to help you with lifestyle and changes that happen as a result of your life experiences and which relies less on the individual and personal interaction and leave the more difficult stuff alone until you feel better able to work with it.