Oki firstly you need to clarify whether you 2 are a couple or not. Throughout your post i did not understand if she said if she likes you too and is ready for a relationship. And you have been noticing her all this while but has she ever even seen you? Do you know when you guys are going to be together? Relationship can only happen through a mutual understanding and consent so find out what is in her mind and heart. Ask her if she is ready to commit to you and listen to what she says. If she makes up some excuse, then she is obviously trying to be nice to you and does not really want a relation.. BUT.. If you guys have a mutual understanding and understand that you are a couple now then why do u care about a guy who had proposed your gal once upon a time. Maybe because they are neighbors she has to think about family commitments too. Havent you ever wondered why she told u about that guy? I mean come on if she was two timing you would she let it out so easy? Maybe she is peaceful and doesn't want to just hurt someone's feelings.. The best solution for you would be if you talk to her about it and tell her honestly about your feelings. Tell her that u have been liking her and are feeling insecure about the presence of this guy in her world and discuss it clearly rather than going through cousins. Girls appreciate honesty so rather than being jealous and living with a doubt, you should have a direct talk rather than talking in riddles and never knowing the answer!