<human>: Can you summarize the given text in a few sentences?

I'm a regular fellow - not striking by any means, except maybe how considerate of others I am. I get called cute often, so I don't think I'm ugly. Athetic physique. 

When I'm not a'courtin someone, I'm confident, relaxed, a couldn't-care-less type. I can be alone and fully happy w/ that for months... in fact, I like to stay home and read or watch movies by myself, eat dinner alone, etc. I'm happy w/ me. 

I err on the relationship plane though.. and I do it big. Go big or go home, eh?? My problem is neediness.. I get wrapped up in the girl I'm interested in/dating. I completely give 100% and where-as that might normally be ok, it isn't. 

I'm insecure in this area.. people have left me my whole life (family, friends for good reasons, lot's of people around me have died, exes) so I get nervous. If I haven't heard from my girl in a few hours, I start to flip. I don't do anything, don't get crazy, my stomach just starts tying into knots. I'm needy, clingy, bah. I need constant reassurance. 

Eventually, I think it's been the cause of the last 7 years of girls walking out. They say different things, but they were never dating the fun, confident, charming guy they met. 

So Reddit.. help? I know I should see a therapist but I'm barely scraping by as is. I understand it's insecurity.. and that I need to learn to trust. Have any of you got advice from your experience here?
<bot>: I'm a needy, clingy bastard looking for help to overcome it and be the fun guy I am outside of a relationship.