The end of the series in season seven is open to interpretations, which was probably the best way to end it. It gave ammunition to both Spuffy and Bangel shippers to use in the battle of "Who does Buffy ultimately end up with?"

Basically, Angel guest stars on the last two episodes of Buffy to give her the amulet that will consume the hero who uses it to save the world. This is where Buffy gives Angel the famous "Cookie Dough" Speech where she explains that she's not sure if she's ready for long-term planning or commitment as far as relationships go.

As for Spike, well, (spoiler) he DOES technically die in the season finale of Buffy. He wears the amulet, and, as previously mentioned, is therefore consumed by its energy in order to save the world. However, in an interesting twist, Lindsey McDonald (from Angel the Series), mails the amulet to Angel's office at Wolfram and Hart in Los Angeles, where Angel opens it and unintentionally resurrects Spike as a vampire ghost. For half of season five of Angel, the Fang Gang scramble to figure out a way to make Spike corporeal again. In the meantime, the banter between Spike and Angel is priceless.

I highly recommend finishing Buffy, or at the very least watching Angel, which (in my own humble opinion) is better than Buffy after season three.

In the comics, Buffy and Angel belong to different companies (Dark Horse and IDW respectively). Because of this, neither Spike nor Angel can (officially) cross-over into the comic Buffy universe, because different companies have rights to the characters. However, that doesn't mean that Buffy can't have a scintillating dream about Spike and Angel in "Long Way Home" (have I mentioned how much I want to blow up that image into a poster and put it on my wall? I LOVE IT!)

Alright, Angel walks away at the end of Season Three and starts his own show! But, if you watched Angel-I didn't I just saw some bits and peices and read descriptions of the episodes-that Buffy, Faith, Willow, Oz and some other people appear on ANGEL, and Angel comes back for a few episodes in different seasons! He came back in SEASON FOUR of BUFFY, and was there just to protect her from some evil! Everyone but Buffy knew he came till the end of the episode! (And I think he comes back in another episode of Season Four and meets Rile-Buffy's boy toy for the season-and they talk! Then he leaves again!)
But they do talk about him in some episodes! Then he comes back in Season Seven at the season Finale, and gives her a gift! Its a necklace that someones supossed to wear that has a soul to take out THE FIRST and his army! An evil demon who can take the form of anyone dead! Spike, Buffy, Angel, Dru, etc. Angel offers him, but Buffy says no! Cause in Season Six, Willow went all evil since her girlfriend Terra from Season Four died, and she got down with the REAL dark magic and went all dark and veiny, Spike ran off to this cave and did three trials to get his soul back so he can impress the Slayer and give her what she deserves! Also, Buffy and Spike slept together in season six! Then in Season Seven, the finale, he gave his life to save Buffy and the others from The First! And apparently that was the end of BUFFY! Untli season eight came out in comics!
But then in ANGEL season five, Angel reveices a box of the necklace he gave Buffy in season seven, and ashes that reveals a very much alive Spike! So that's all I know if he dies or not! You'd have to watch SEASONS Four-Seven of BUFFY and watch ANGEL seasons one-five (like I'm gonna do soon) to know EVERYTHING! (Season six of ANGEL is in comics as well as Buffy Season Eight!)

Buffy has 2 boyfriends after Angel leaves. One of them is a TA at Buffys collage and the other is Spike. Angel moves to Los Angelus and starts a detective agency with Cordelia chase and a half demon named Doyle. Spike dies while trying to save the world. Everyone thinks he is dead untill he returns as a ghost in Angels office in Los Angelus. Buffy moves to Rome and falls in love with a creature known as The Immortal.

just collected alowed of buffys and angels dvds from our retailer for 7.99 and i am half way through most of the epesodes so far so i have know idea what happens to my baby spike