Why "Good Things" always end so fast and quick?

After the breakup, things started to slow down alot. Everything I do, I felt I was alone. Watch movie, eat my meals and going out even though I was with my friends/family. Come to think of it, we started only half a month after we know each other. I not 100% percent sure she is truth to me but I'm almost 100% percent sure I'm real to her. Our love is foolish/silly but was remembrance one. Tragedy happened, I saw her with another guy. I don't want to comment anything about her. Reality is real, I got to face it. Even MSN I see her nick - Money, Work, Office Politics, Study, Driving, Family, Love.... I'm so occupied!. The word "Love" appeared so fast after we broke off 3 to 4 weeks ago. I get to see the real her when breakup. I was thinking perhaps she isn't the one. Though she treat me like that, I still hope she find what she want. All the best. Even though I have only 4 to 5 gfs, I still liked the first one. I missed her. We didn't keep contact since we breakup. We were both naive, our love is true. I can feel her love for me. Is just that I felt I'm not good enough for her so I left her. We lived in the same area but I moved out of there due to some reasons. And when you are "sway", you really is "sway" to the max, I lost her contact number, maybe this is fate. God wants me to know more before making my choice? maybe. Now that I'm better off, I hope I can meet her just one more time to fulfill my wish. I hoped she is single.:)