Karen, the kind of problems you're having with the plumbing in your trailer are going to be extremely difficult for anyone on a forum to help you fix. There are just too many things that can go wrong, and from the sound of it your trailer has many issues that need to be resolved.
I would recommend that you get someone local who can put their hands and eyes on things to help you get your problems under control. If you're living in the trailer full-time you need to do this quickly, because unfixed water leaks are the death of RV's. The materials used to build them don't hold up to being soaked with water for long. You could very easily end up living in a trailer that is literally rotting away around you, technically uninhabitable, too expensive to fix, and of no value for sale or trade.
I wish you the best of luck.
:):)
