For perspective: in my first job I had to take a week off to travel to my family because I was worried my dad was dying. We spend a week and he pulled through. At the time I thought it incredibly generous that my manager could manage without me for the full week on such short notice.

Of course the two are in no way comparable emotionally, but it's a similar scenario of needing time off to cope emotionally. Some companies are terrible and some are open and flexible - any time over 1 - 2 weeks time off given without complaint is a blessing and a sign your company cares about you. Pushing for more than 12 weeks is.... well, it's not realistic and it's stretching what you can expect.