My parents getting old and me being fusional

I see my parents ageing and getting weaker and weaker and I feel desperate.

I often wake up during the night feeling terribly sad about this. They are my world, they have always been there!

I have my own home, but I’m always with them, always hugging them, not even thinking about marrying or having a boyfriend because I feel like I would betray them and miss the good moments I still can share with them.

They are not complaining, this situation seems to accommodate them, but sometimes they tell me that I should go and live my live (but not in a convinced way !).  I believe they would love to have grandchildren, but given my mental state, it’s not going to happen anytime soon.

Could you please helpful me put things in perspective. I cannot understand why I am thinking this way. My friends are not that fusional with their parents.

Maybe it’s the fact that they came from a foreign land. Life was not easy for my mother, she made a lot of sacrifices for my brother and I. When I was younger I made the promise to help her with money, to never give her up and to make her forget about her lost and hard youth. I also remember my father treating her so bad, and they are still together (she doesn’t have the money to live somewhere else, and I cannot afford to pay another rent for her). But the fact that he is now getting weaker while I still remember how young and strong he was breaks my heart.