Kashmire went off feed for 4 1/2 months and he just started eating again a few weeks ago. I ceased all handling of him, other than a weekly weighing and to move him if needed to another part of the viv when I was spot cleaning. I also filled his viv with loosely balled newspaper until he ate again, then slowly weaned him off the newspaper.
Another thing that's been suggested to me is to cycle the lights - 14 hours of light, 10 hours of dark to simulate warmer weather time of year.
I agree though, get the lower end of each temp range up.
I think we as keepers stress more about the fast than the snake does. It is a relief when they start feeding again!