What to do with my old bike?
If I do not easily notice a bent frame at first sight, it tells me it cannot not be that bad to compromise the frame integrity. When you ride the bike, do you feel it handling weird, or shaky? if it doesn't, then I would conclude the bent frame is inconsequential. Personally, one of my bikes has a bent frame which I didn't noticed it for the first few months. Been riding it for 4 years since then and it's never been issue in handling or otherwise and I've ridden in long rides (15-20+ miles) and at considerable speeds (17-19 mph)

The loose hub, as it has been mentioned before, it could as easy as tightening the bearings cups or as bad as needing a new hub. Without a video or personally inspecting it, it hard to give proper advice. 

If the frame is toasted, I would consider two options: donate it to a bike co-op so it can be used for spare parts; or find a similar bike on CL and keep this one for spare parts.

Also, a bike co-op will work with you to either fix your bike or allow you to pick another one in exchange for the one you have.