<human>: Can you succinctly summarize the text in 1-3 sentences?

I've heard and read of how every one has the "One that got away" or the one person they never truly get over. My question is, if everyone always has someone they are pining for all there life, that they can't have, does real love even exist?
 I understand caring for your exes but to completely want and love one? What's the point in love if the guy I want to be with, always wants someone else. Sure he might love me, but there will always be that one person who I would be dropped for if they happened to show back up. I don't want to be settled for, or used as a replacement, I want to be loved truly. Maybe I will always have that one person I always want more than anyone else, I hope I don't. If this is true, then honestly whats the point? If you can't be loved completely, if you can only be loved half-way, why bother?

I want to be a guy's one and only, I want him to love me and want me, not love me just for the sake of not being alone, not have me but always have another woman in his thoughts, not kiss me while he wishes it was her instead. I want to be the one in his thoughts. Maybe that's selfish of me. 

It scares me because I could find someone I love completely and never know that in their mind there is always another girl. That terrifies me so much to the point where I'm afraid to love. 

I'm also scared that I will always pine for my ex, that I won't be able to fully love again like I did with that first one when he was the only one in my thoughts, the only one I wanted. It makes me sad. I hope I can love that way again for someone else but I'm starting to feel like I never will, like he will always be in my mind and I will always want him no matter what and that makes me feel awful. It makes me feel as though I shouldn't get into another relationship ever again because it wouldn't be fair to the other person and I would feel wrong.
<bot>: I'm confused and depressed. I feel like I'll have to settle for a lesser type of love or be alone.