Well, the way i see it, many 'lesbians' seem to choose this path out of an anger towards men. Perhaps abused by a man as a child, or repeated broken hearts, or both. So these women choose to be 'lesbians' more out of anger towards men than a genuine affection to women. So their goal is to stay away from men in general.
Before anyone argues, note i did not say all homosexuality is a choice, so don't twist my words and start badgering me on your opinion.