I am so sorry to hear about your physical symptoms, your fear of going to the doctor in a few days, and about your husband's infidelity. We are here if you would like to talk about any/all of these subjects more, and there is an entire community of women who are going through many similar situations.
1. I am not sure why you have self-diagnosed as having Trich, as your symptoms do not match this condition. The small bumps indicate something else, and to ease your fear of going to the doctor, they may or may not be sexually transmitted. It is best to just go to your appointment with your list of symptoms, detailing when they flare up, what the triggers are and how long you have noticed them. You may find this information helpful: Dealing with bumps "down there".
2. Here is some information about sexually transmitted diseases (STDs) and infections (STIs) that you may find helpful: STD Testing.
I am concerned that you said your husband gets a "little violent" when he is angry, and you saying that you "feel stuck" must be a scary combination. There are thousands of women who feel stuck, are in marriages that are unhealthy or even violent, and there IS a way out. Here is some information and resources for you; there are people who can help you if you just call them and talk: The National Domestic Violence Hotline: 1-800-799-SAFE (7233)
Many women are in situations where they are home with the kids, do not have any money in their name, do not have means to their own income, and these women are able to call the NDVH, talk with someone, and make a plan to help themselves and their children.
Please let us know how we can help. Do you have a good support system nearby (friends, family)?
Please let us know how your doctor appointment goes on the 5th. You can also talk to your doctor about any emotional or physical violence (regardless how "little" it is) and they have excellent resources as well. No one will pressure you to make a decision; it is just information-seeking you are doing right now. Your doctor should also be non-judgmental about any bumps or infections you have, regardless if they are sexually-transmitted or not. Doctors have seen everything, and are there to help us get better.
Take care, and please let us know how you are doing!