Hi Linda -
As Roseanne Rosannadanna's father used to say, "It's always something" (think SNL and Gilda Radner) and that's never more true than with early and mid-stage Alzheimer's. It's amazing your DH didn't go through the glass. Maybe some of those plastic decorations that you can put on windows would help him see the slider. Maybe he could be pursuaded to wear a baseball cap and that would protect a bit from branches and sliding glass doors. Maybe? Good luck!
My sweet little mother was in mid-stage when I moved her to an assisted living facility because there were more people to watch over her there and keep her safe. As Sally, Martha, and Barb can attest, it's really, really hard to do it at home by yourself. You just cannot be awake all of the time. Sooner or later, your DH will become more than you can handle. Sad, but true.
My personal opinion here, but as far a medications go for Alzheimer's patients, my belief is that whatever gets everyone a good night's sleep is good. Beyond that, if an antidepressant helps, go for it! There's no cure and it's all about doing the best you can one day at a time. Maybe you should talk to his doctor about some medicine to give as needed for aggitation and restlessness. I know you don't want your DH as zoned as a zombie, but judicious use of meds. will avoid that state.
Rant as needed!!
Wishing you well - Barbara