I know how you feel, I have been there hundreds of times. There is absolutely nothing you can do about the past, you can only work on what you will do moving forward. AA is not the only way. It is helpful for a lot of people though, I hope some of those who are very active will come on soon and explain it better to you.
At this point I would not rule anything out, why not give a try? You got yourself to rehab, surely you can get yourself to a meeting. Call the local number and ask if someone can pick you up if you are afraid to go by yourself. You don't have to do or say anything, you can just listen and see if anything resonates with you.
Otherwise there are SMART meetings, which I have no access to where I am so I know little about but again, someone else should be here with further information.
My personal feeling is that you would benefit tremendously from seeing a psychologist. Do you have the means to do so?