I would guess the answer would be "not very many if any at all," and there is a reason for this. Episodic TV doesn't do this very well - not with its main characters. And the reason is just what I've said earlier: writers might be capable of dealing with it adequately (that is, they are talented enough to deal with it adequately), but TV shows aren't good at it, and viewers aren't either. Some of us can cope with seeing our favorite characters saddened but then made stronger by grief; we would not cope well with seeing them devastated and broken by grief.
I don't really think you would cope with it that well either, Tomalak. I could be wrong since I know you not at all, but it's hard for me to imagine myself or anybody else wanting to watch a character they know and care about being grief-striken week after week. And that's what it would take to deal in anything like a realistic manner with the death of a child, the rape of oneself or one's spouse, etc. I don't personally think that episodic television deals very well with the death of a spouse, either - but they do try that from time to time.
Examining deep, overwhelming grief is a subject that works in some forms of fiction, but I really don't think it works on a weekly TV show whose characters we get to know intimately. Shows, as far as I can recall (and my memory isn't perfect) that have dealt with such issues use non-regular characters, or they are shows where the characters aren't deeply explored (I'm thinking of police dramas here, which often do touch on major issues, but only as the B- or C-plot) or they deal with it very badly.