The X-Men Fatality Timeline (4th Draft) nicely exemplifies why it is so hard to take superhero comics seriously.

Jean Grey's "Deaths": The Full Listing

And, in honor of Jean Grey’s special status as the Grand Champion of my X-Men Fatality Timeline, here is a complete listing of the relevant issues and how many times she “died” in each story, to save you the trouble of searching through this post line by line to sort them all out for yourself. Stories that may not even mention Jean Grey (or Marvel Girl, or Phoenix, or whatever), but that killed her just the same (along with zillions of others) if you take them at face value, will have “(Implicit)” after the issue number to help you distinguish.

1 in Doctor Strange #12 (Implicit)
1 in Marvel Two-In-One #7. (Implicit)
1 in UXM #107. (Implicit)
1 in UXM #108. (Implicit)
1 in UXM #113 (in the opinion of most of her fellow X-Men for the next 12 issues)
1 in UXM #137 (As everyone believed at the time, and for the next five years)
5 in Avengers #314 (Implicit)
1 in Infinity Gauntlet #2
1 in UXM #281
1 in Mys-Tech Wars #3
1 in The Adventures of Cyclops and Phoenix #1 (soul separated from her own body for a solid twelve years, from her point of view!)
1 just before the start of Captain Marvel #6 (fourth series) (Implicit)
1 in New X-Men #148
1 in New X-Men #150
8 times (at least!) in Phoenix: Endsong #3.

Grand Total: 26. (16 Explicit. 10 Implicit.)