I can think of 2

chrissy rock (who is 1 of my fave actresses), played a hotel manager called janey york in the tv series benidorm (UK comedy)

after 4 series of the show, the writer didn't want to write anymore episodes, but when the channel convinced him, he did write more episodes (but decided not to bring back janey york)

I was really upset by it, to the point where I started looking on amazon for dvds of her in other things (things that actually sounded boring), but needed to get it just to see her act and hear her voice

as for benidorm, I did eventually start rewatching it (please don't kill of jeff though!)

the other one was cammeron murray in a soap opera I watched.

I loved him, and when he went to prison, it was announced that he'd been written out the script and would not be returning

so, I felt really sad about it, and went about creating my own peace of fan fiction- what would happen to cammeron if he was still here?

I also found the actor's name, and found he was in a police drama so I started watching that, which sort of took my mind off the fan fiction.

again, I did start rewatching the programme, but like a year after he quit the show (and I felt so guilty for missing so much)

actually a third example

becky from tv series utopia

at the end of the second series, she turned in to a zombie, then the channel canceled the show and i was on the edge of my seat.. you're not gonna tell us what happens to her next?. you're not gonna make a third series?