Right, there’s no wrong decision. The only wrong move was thinking shhe might change she’s clearly moved on. I hate to say it, but you’d be better off getting a lawyer.
Save every piece of evidence you have so you don’t lose anything. If she finds out you’re filing for divorce and you have no proof she cheated, was still talking to someone afterward, or threatens to take you to the cleaners once she’s on her feet, things could get messy.
Prayers it works out for you, brother.