Reply #103: It's not all about you.

[Gormy Cuss]

Why do you assume that being told you're nice but she's not interested is a statement on your character? Maybe she's still got feelings for someone else and didn't realize that until after she tried to date again (and no, she isn't obligated to tell that to someone she just met, even if he is a nice guy.) Maybe she has enough manners to try to keep the date pleasant in spite of the fact that she didn't really agree with you about much of anything. There are a lot of reasons why after one date that someone doesn't want to repeat the experience. If you think being called nice is emasculating, wait until you encounter someone who is brutally honest. "You're too short." You're going bald." "You don't have enough career ambition." "You live at home, you must have mommy issues."
I could go on, but I think you get the picture. When a woman says that you're nice it's a compliment.
Deal with it as such. You'll feel better about yourself that way.