Sounds as if your previous experience with these is limited. The efforts expended on the door thus far have made it worse. First check the height of the door. Standard house doors are 6' 8"- 80inches. Some mobile home doors are shorter. If yours is standard, a new one can be bought from Lowes or Home Depot. If shorter, the mobile home supplier is the only choice. The new door assembly must be properly installed to be satisfactory and raintight. Perhaps an experienced person could repair yours.

I agree with bus driver that any new standard door you buy most likely will NOT fit. MH doors are shorter. LOWES, HD will not have a door you need. Go to a local MH supplier and get the proper fit door or the closest to it. Remove the old door and the frame. Since the frame is moving you probably will need the replace the studs on either side and above. Measure 3 times and cut once. Get the first stud in and set the door with frame along that and mark the other side. Make sure the first stud is plumb. You'll need caulking everywhere.