You are NOT alone I feel the same way. I really think they're unhealthy for each other as much as I love them. My ideal for them is breaking up in high school and getting back together when they're like, 40-50 years old.
I wish people were more willing to take their early conversations into account as characterization of their relationship as opposed to fully portraying them as "out of character" or "irrelevant". They're still important!
Everybody needs to hear someone say “Nobody else will do. It has to be you", even if it's just once in their lives. As long as you can feel sure those words were sincere, you can live through anything, no matter how painful.