I'm so sorry you are in this situation. Wish I knew what to say that would help. The whole things must be so stressful for you!

There are psychologists who believe that subconscious needs bind people together more strongly than any other factors. Perhaps that theory is false, I don't know.

My parents didn't have many interests in common and fought like cats and dogs and people predicted that their relationship would never last and yet they were married for 50 years. Perhaps there was something very deep holding them together?

If I read you correctly, and my English is not all that good, you are asking a question about how one can do things in the present to guarantee a desired future outcome or at least increase the odds of a desired future outcome. Sadly I don't know the answer to that.

I would think [perhaps wrongly] that if you meet your girlfriend's deepest needs, then your relationship can survive all the ups and downs you mentioned.

I must confess to ignorance here. Hopefully other members on these Forums; members with more knowledge, experience and insight will see your post and respond to it with better words than my poor words.

My heart goes out to you and I hope that things work out for the very best for you! You are in a tough stop to put it mildly and it seems that you are thoughtful and trying to do all the right things!