Hi Craig,
Sorry for the late reply, I've been away for a while visiting family in Ireland.
As far as cutting people out of your life goes, it's a good idea to have a purge every so often. A lot of times you will find that you are spending time with people you just don't like, sometimes they're nice people, sometimes they are assholes. With the nice ones it's not fair on them to continue the friendship, so let them down gently. With the assholes, it's not fair on YOU to continue the friendship, so just get rid of them, unceremoniously if necessary. A lot of the problem I have is devoting time to spending time with people I just don't like and with whom I gain nothing from spending that time because I feel obliged to. The thing you need to learn is you are not obliged to spend time with anyone. Give your time to people who you find interesting and stimulating, and who give something back. You will sometimes find that you can improve your quality of life significantly by cutting ties with even whole groups of people. Sure it's difficult at first to just cut people off, but in time, especially with the ones who f***ed you around and used you, that you feel better for getting them out of your life. In the process you often find that people you didn't really consider friends become the ones you are close with. For example, I recently started talking to this guy I used to work with who I always thought was a little slow and a bit dumb, well shame on me, because we've been hanging out a lot lately and he has a quality I really appreciate, he's loyal as all hell. He always treats you as an equal and is an all round nice and funny guy, sure he's no genius, but I don't care about that because he's always so upbeat and fun. Sometimes you connect with the people you thought you would the least.
James