Would you rather:
1) Marry someone you don't love, but that person loves you unconditionally
OR
2) Marry someone who you love unconditionally, but they don't love you back?
#1 because free will. I would protect someone who loved me unconditionally with my life. I could (would!) learn to love someone like that.
I cannot teach someone else to love me who doesn't. And someone who despised me would teach me instead not to love her, and would make me into a worse person. (And it's debatable whether I'm even a good person as I am, now.)