I think I can relate, when i use to be with this girl, I loved having her around and it got stressful for me when I thought of her leaving anywhere, but when she was away on holidays with her family I knew she was safe and wasn't going to replace me cause its a family holiday, so then I was worried about her coming back and potentially finding someone else and abandoning me. is this what you mean? if so you're definitely not alone with this.

I cant say I ever found a solution though :/ I was forced to cut her out of my life and now I miss having a female friend/partner/associate of some sort as well.