Learning to not believe in stuff you no longer believe in is a long process. Ive found that deliberately exposing myself to such things, participating in intellectual debates and doing readings on the subject that bothred me has helped immensely. Discussing it with a close friend or the board is certainly not to be overloooked either.
I find when you encounter a hang up it helps to ask yourself. WHY does it bother me, WHAT about it is causing me to react in this way and is that in fact RATIONAL. If it's not rational get a piece of paper and write down all the thoughts and fears you have on the subject as a sort of mental association, don't hesitate and dont think about your answers. Re-read it when you are done and think about whether there is any merit to these or if they are perhaps aspects of your life you want to let go of. Reasoning through it every time it comes up really helps a lot more I found than being disgusted by my reaction and not probing it any deeper.
I commend you on taking a positive and tolerant attitude, it's a big step in the right direction of making yourself into the kind of person you want to be.
As far as feeling isolated that is natual. High control groups have a "Socialization" process. On exiting these groups it is normal to feel the need to be re-socialized into the real world. It is a long process and not always an easy one but it will come, just dont give up on it. Also consider that everyone has different needs for people in their lives. Some are happier with a few friends, others require being surrounded by many more people. Think about what is right for you and perhaps work on just involving one more person in your life at a time. Hugs.