I'm with Redlemon. If I have a captivating book to read, I can escape anywhere. I find the best place to read is in bed, because it's cozy and warm. Reading in a quiet room as the sunlight fades, can do wonders for you.
In a similar vein, I also find attending a matinee movie in an empty theatre very relaxing.
Now just because nobody has mentioned it yet, I'd also like to put in a few kind words for the humble
Bathroom.
It's absolutely private and everyone respects that. Whether your in there taking a bath, sitting on the toilet, or passed out on the floor, time comes to stop.