Tub /tile leak

I have water damage at each end of my tub at the wall and on the floor. I cant keep a caulk seal because the tub is giving a little when there is any weight in it and the seal around the tile breaks, it seems like water is leaking behind the tile to the floor under the tub, or around the lip of the tub and being absorbed by the drywall behind the tile, hense ruining my walls! Any solutions with out completely removing my tub and destroying tile?