YOu are not snooping. You are in your own house. You are still married. There is nothing to hide right.
I think you have your answer already. I would put a keylogger on the computer. You will verify your answer very quickly.
If your going to get angry and physical. Then you need to leave. Until you calm down. Then you need to make sure that you are never alone with her until you can handle your emotions.
Flowers always make people better, happier, and more helpful; they are sunshine, food and medicine for the soul. unconditional love is awesome!