Weird electrical problems driving me crazy!!!

[Lee in Ottawa]

Hey guys, I'm losing my mind with new problems poppying up everyday.
Heres the scoop maybe maybe you guys will have some feedback..

First off its a 01 f350 dually.

One day out of nowhere it didn't want to start and it seemed like the batteries were dead but would eventually start and run perfect, the gauges show the batteries are good.

Anyways then when i went to start it and it wouldn't turn over at all i tired it again and it turned over no problem but the starter made a whining noise. It did that for a few days.

Next problem was all of a sudden my trailer brake controller lit up and it only lights up when the trailer is plugged in which it wasn't. Than it was back to barely starting and seemed like the batteries were dead sometimes it would start fine.

And finally last night it started fine but every light but the headlights and brake lights were out.

I have no idea what's going on.

My best guess is that the starter is maybe on it's way out (but seems fine now) and perhaps there's a short in the trailer wiring. And i'm at a lost on the lights.

Any help
Any help