We don't need to keep rehashing a fictional 16 year old girl's high school relationship with an older "dangerous" man. How many people live happily ever after with someone they dated for a few months when they were a teenager? We can let Buffy have a mature, age appropriate adult relationship with someone new atp can't we?

Drusilla was established as Spike's sire on the Buffy long before it was "clarified" on Angel. Check episode "Fool For Love" Sn 5, ep7. It was a plot point before he ed Angel. Drusilla was not always sickly, she became weakened relatively close to the contemporary time line in the show. Before that it was established she was pretty much as terrifyingly awful as Angel and Darla. I also think it makes more sense for Dru to be Spike's sire because Angel and Spike hold a lot of animosity for each other that likely wouldn't exist if it wasn't for the love triangle between the three. Spike's obsession with Buffy is like Spike trying to get back at Angel for Angel constantly staking ownership over Drusilla. Also it's pretty clear that sireship in the show creates a sort of reverent bond between two vampires, one that Darla has with the master, Angel has with Darla, Drusilla has with Angel and Spike has with Drusilla. No such bond with Angel and Spike exists. The line about Angel being Spike's sire on his first appearance feels more like a technical error than an intention considering their history.