Good job on getting her number and meeting up with her a few times. But she may have just been trying to get rid of you with the threesome talk... how do you know it really happend if you were not there? First thing you have to learn about dating is that when a girl makes an excuse not to see you, no matter how rational the excuse seems, she is blowing you off - she is not attracted to you. As soon as you get that, tell her something came up... and on your way home, call or hit up another girl... don't put all your eggs in one basket. Always try to estimate their love level and reject them before they reject you, and you will always have fun with women and never get any major rejection... or divorce, for that matter.
When a woman says, "He was not my type", what she really means is that she did not find him attractive.