I have to agree with Jan. There could be a whole host of reasons why the support you expected hasn't been forthcoming. People have their own lives to live, their own issues with which they must contend, and their own dramas they need to try to manage leaving little time for the lives, issues and dramas of others. Reading people and/or interpreting silence is a dodgy business even under ideal circumstances. Of course, you may be right about the individual but even if you are there is little (virtually nothing save for the momentary pleasure of getting your own back) to be gained by burning bridges. If the person has moved on, so must you. However, slamming the door on the way out doesn't accomplish anything. It would be better to leave the door of communication open and just concentrate on building relationships with others. You never know, she may come round some day.