What chainring in front is the chain on when it rubs - inner or outer? If it's on the outer chainring - inner cassette sprocket combos, some times it's tough to get rid of that, but see the next question below.

From what you've written, it sounds like it worked OK for a while then developed this rub? Could be as simple as the FD has been twisted a little and the tail end is too far inward and rubbing. Check that alignment first. Or better yet, download FD installation and adjustment instructions and go through it precisely, step by step, starting at step #1 .

I doubt if a bent RD hanger would cause rub with the FD - a bent hanger does not affect the cassette, only the RD shifting. It's the cassette - chainring - FD relationship that causes FD rubbing. If your rear shifting is OK and the RD is aligned with the faces of the cassette sprockets, it's probably fine.