You're lacking options /abundance and confidence in yourself and the idea that women greatly desire you.
So when she pulls away, instead of realizing what might be causing it, you start to feel bad about yourself.
Me, I know what women want and i know how to take advantage of that. If a woman pulls away, I know that i might be showing her signs that im not as interested or that im not the right type of guy for her, or will b reak her heart, play her, etc.
I'd learn to not care and realize just as easily as you found her, u can find much better. Knowing this is crucial. I've had some of the hottest women leave my life and when I was younger I used to think "man idk if ill find a girl like her" which was pathetic because then the next girl I found after her was much hotter/better. Its a weird thing..
The only hard part about this is you've been locked in with her for 5 years. Since I never had anything that lasted that long, I'm going to bow out of giving any further advice.