What I´m about to write might seem cruel, but please believe me when I say that I write it in order to try and help: I think that if I were in J´s position, it would give me the heebie-jeebies!
I feel able to write that because YOU realise that there´s a problem, and are willing to consider that it´s not all J´s fault. You sound like somebody I´d define as a "clinging ivy". And I think that you really need to work on your own issues before you tackle the relationship ones.
I used to have a HUGE inferiority complex / insecurity. I KNOW that it´s difficult for other people to deal with.
It´s a disaster to expect one person to provide you with EVERYTHING. You´ll make that person feel claustrophobic.
I get this strong signal that you need to learn to love yourself, to have faith in yourself. And to stop trying to get ALL your emotional needs supplied by J. Try to get a DVD copy of "Scorchers" by David Beaird, and pay attention to the transformation in Talbot. Her husband of just 6 months has lost all interest in her, UNTIL...
I wish you all the best.