There's a definate downturn between Willow and the others at the end of season 6.
The only characters to appear in more episodes are Angel (166), Willow (147), Buffy (146), Xander (143), Giles (121), Spike (120) and Wesley (109). Allison Hannigan is in all 144 episodes of BtVS Nicholas Brendon is in 143. However, Buffy insists on fighting Caleb alone, and slices him across the stomach, apparently killing him.

Heck maybe Riley divorces with his wife and comes back to the Buffster and they make with the smoochies and end up marrying! It's … The magic opened Willow up to the pain of the world, and she attempted to start the apocalypse in an effort to end the suffering.

However in the final Series of Angel she gets with the Immortal. In Buffy the Vampire Slayer she doesn't end up with anyone.
If you want her to end up with Angel, that's how it goes for you. But it also left her open to Xander’s pleas to stop which reached her humanity.

Their friendship strengthens and weakens and points thoughout the series but it's always there.

The Buffy story would not be continued beyond this point until "The Long Way Home", a comic book, in 2007 and the Buffy and Angel saga would end in the Season Twelve series in late 2018. Maybe Parker comes back and they get back together. Coincidentally, Charisma Carpenter shares the same initials with her character. If it's Spike, that's how it goes for you. By smashing the Seed, Buffy effectively resets much of the world-building Season 8 had done, which had created a much more supernatural Buffy-verse. Suddenly, Caleb shows up from behind the woman, kills her, and almost has Buffy bested when Angel steps in to save her.

The next day, Buffy asks Willow if she'd like to go out that night, but her experience with her vampire double has made her "feel like staying in, and doing homework, and flossing, and dying a virgin," in order to make up for the "double guilt coupons" Vampire Willow has accumulated. Willow and Xander are with Buffy right up to the final episode of season 7. Though she tries to avoid doing this, knowing it will ruin the lives of so many, including Willow, in the end she is left with no choice.