Seal wearing off paint on top of rear shell

[RockyMtnRay]

When I was putting away my TM yesterday after unpacking it from a trip I noticed the rear seal on the front shell had completely worn through the paint in two spots on the top of the rear shell. The two spots were about 3 inches wide, respectively about 6 inches and 12 inches in from the curb (door) side of the trailer. Plus the seal had worn through the paint on the top trim piece (this I know is pretty common) and is distinctly wearing on the paint across the rest of the rear seal.

Obviously I'm going to have put extra effort into removing dirt/grime from the roof as I suspect that is acting as an abrasive. I should add that the roof is getting a thorough cleaning after about every 4th camping day and the trailer is stowed in my garage between trips so it's actually staying pretty clean.

I don't recall much mention of this problem so I'm not sure if this is a unique issue or not. In any case, does anyone have any suggestions for (1) an abrasion resistant primer/paint I can fix the top with and (2) any suggestions for some kind of abrasion resistant cross-roof coating or film to put under the seal contact area? I was thinking something along the lines of the 3M "Clear Bra" film or perhaps using one of the rubber roof treatments to provide additional protection for the roof.