<human>: -I started dating this girl (24F)  on year 2005, then we broke up after 3 years because of long distance.

-On year 2008 I dated this girl(24F) who I really loved and I wanted to marry her but she cheated on me. 

-Then I dated the 3rd (25F) one and during that relationship I was dating other multiple girls because I just wasnt feel any love anymore

-later on I got to bachelor degree and I found another girl(24F) who I fell inlove with my whole heart and I broke up with all other girls (now 4) to start persuing her. She told me she in love with someone else. 

-I persued her for 3 years despite that fact. I once slept with her and we kissed. She once told me she loves me. But when it really matters. .she always picks the other guy before me. Always.

-now im single, I dont want to go back to to those girls. I am tired of chasing this one , but I really love her from my heart and I cant get over her.

-I feel so bad I cant be with someone I love. I feel Im late, my friends are starting to get married.i feel lost after deciding she cant be with me I feel I have wasted my time, I feel useless and lost.
Please tell me what to do....what to think. Anything please.

Can you condense the text into a few key points?
<bot>: I have dated girls I dont love, now I find the one I love she is rejecting me, I feel to go back to old ways, I feel useless, I feel im chasing a wind. Help advise whay to do.