Shower Door Leaning

[stephen_hayne]

Hi, I have a frame-less glass shower door that is leaning off the wall. I have access to the backside through drywall and think that I should brace the wall. The shower is tile, 2 layers of schluter, and cement board. There is a 2x6 on its face where the hinges are but its not holding the weight. Inside the wall, there is also a plumbing stack directly next to the 2x6 so I can't just add more wood. Picture is attached.

The shower gets worse in the summer and the door actually hits the adjacent satellite piece. Right now, with winter things have have tightened up and they aren't hitting.

I thought I would span across two studs with steel and maybe brace things from the backside. Any ideas?

Thanks!