The problem is that I have autism. I do not have a natural empathy. So I need to know rules about what to say or do so I do not hurt people. Believing in a god actually helps me not to be the violent bad person that my feelings want me to be.
Autism does not mean you do not have a natural empathy. Every autistic person is unique, many have far too much empathy. I think what you are most likely referring to is Theory of Mind. If you are meaning that you lack empathy, I suggest you make absolutely sure after a very thorough introspection that this is correct. Because for decades it has been taught that the autistic lack empathy and this has condemned many people to self-doubt- needlessly. Many clinicians are flat out WRONG about the autistic. Autistics are not clones, with each having the same symptoms or requiring the same accommodations. As they say, if you have met one autistic person, you have met ONE autistic person.
The rules you are referring to are found in many other places besides religion. I understand the attraction of Islamic structure, but unfortunately it takes it's own rules to extremes. The moral stipulations of Islamic practice when perfectly practiced (extremism) actually reach a place of division of the community. So please do not follow rules that are not ethical, as these do communities more harm than good.
Find a middle path if you must follow rules, and ensure that the rules you do follow are to the benefit of your community. Screen them yourself.
Where to find these rules? Rules of community living are far simpler than those mysterious social rules that no one talks about or that contradict each other. Read up on your local laws, and study ethics. Remember the things your mother and teachers instructed you when you were a child (assuming they were not abusive folk). Children's shows and books are a goldmine of the basics, including social skills.
I understand your frustration.
The best community to find support in is the autistic community. Look for a local meetup.