A lot of it probably comes from deeply negative personal experiences, combined with a general propensity for people to apply a categorical belief to particular experiences. People who were treated badly by a particular group of Christians, or people who see and hear about certain Christians advocating for some terrible politician or political goal, are applying a generalized belief to how all Christians act, and potentially to all religion in general. It’s much harder to accept that the world is a deeply complicated and messy place and that religion and religious belief is a much more complex element of human civilization, culture, and personal identity than what many people would care to acknowledge.
So your assertions here are the following:
So, point by point:
If you want to hate religion because you’re bitter, that’s fine. You can feel about religion any way that you want. But don’t be offended when you bring it up out of nowhere and someone tells you that your comments are irrelevant to the current discussion.
The world doesn’t revolve around your personal bitterness.