I think part of the reason we see a pattern of Christian Bashing (if I may title it such), is that a lot of us do have negative experiences with individuals of, or even whole groups/churches, who count themselves among the Christian faith. Still more of us may be coming from a background in the faith (either our own previous involvement or mere family connections). In either case, it is part of our severance from these past relations and to that extent perhaps normal and even necessary.
However, this does not make it any kinder, any less prejudice, or justify our words or actions in the least. It is a delicate balance we must strike, to be able to disconnect from the church and express our negative feelings towards the religion, while maintaining a polite and hopefully kind manner.
I had to find myself a group of people sharing a similar state of severance. We shared our pain and anger, and helped one another to eventually grow above and beyond this to a place where I am proud to say that I can count among my friends Christians as well as Atheists, Pagans, Buddhists, etc. I regard each path as equally valid, and am able to find no offense, fear, or anger when faced with any of them.
My advise is, try to find a safe haven in which you can work through your emotions. Whether this be with friends in person, a group online, or just between yourself and your journal, you need time to vent so that you can move on. Just like when ending any relationship.