Hi Tristian,
The answer is in your question ....in two ways...
1. You say "my relationships have all ended because of me being oversensitive and clingy. I've tried to not be so sensitive and clingy"...you haven't tried hard enough...OR..you haven't gone about it in the right way to make the change effective.
2.You say "my relationships have all ended because of me being oversensitive and clingy.....I've tried to not be so sensitive and clingy but it just seems that's who I am."
Think that you are, or think that you're not...you are always right!
You need to reframe your solution to take account of the fact that your behaviour is one of passive control...your need to gain control of your life by controllong others. This is not healthy. So change it now.
The approach you could adopt to be more successful in your approach would be... think of a role model of someone you see or think of as being self-assured,and confident around others allowing them to do their own things. Someone who takes responsibility for themselves, is independent, non-judgemental and takes accountability for their own actions. Then begin to adopt their actions, behaviours and mood states.
Good Luck!
Contact me if you encounter any difficulties and I'll try to suggest other ways forward, should you need them.
Donna, thank you for all that advice. I'll definitely try to start keeping a journal on my relationships. It sounds like a way to look back on what I did right and wrong. I'm gonna have to look up that book too. I hope Barnes and Noble has it because then I can get it as an ebook and carry it around everywhere I go because I'm getting an ipod touch for my b-day and Barnes and Noble has an ereader app for it. I'll also keep in touch with how everything is going. I already feel very welcomed here.