[Yuffa]

I think it is important to identify this 'feeling' you have for your friend. In reality we often want and desire what we can't have.

Could your friend's perfect gf/wife image be just an imagination of what you THINK would be like to have a relationship with her?

Given that she doesn't seem to be able to keep a long term relationship at this point; could you really be the one that could tie her down?