I'm thinking of leaving my wife of 3 years because she is angry at me all the time
Why is your wife always angry with you?
Only for silly things that don't matter in the long run.
You need to sit her down and talk about how you feel and try to work things out. Bottling up emotions is very bad for the mental health. Go to marriage counseling if you need it.
I just need to get over it and make it happen.
Sitting down and having a talk can be hard even with a partner. Just make sure if it starts to get heated to take a break and walk away so everyone can cool down. Do not rule out getting professional help either.