I think most of these are close to what you want. I wasn't sure if memory problems were something you didn't want so I included a few with that detail.
When We Dance ---- by Pepperlandgirl http://www.nocturnal-light.net/fanfiction/story/178/When_We_Dance/allhttp://www.nocturnal-light.net/fanfiction/story/178/1/When_We_DanceSummary: Spike returns to Sunnydale five years after he left to get his soul. Buffy's with Angel and he has a new love of his own---but some things never change. And oh yeah, the world's ending (again).
In the End ---- by Moluvsnumber17http://spikeluver.com/SpuffyRealm/viewstory.php?sid=33772&textsize=0&chapter=1Summary: It's been five years. She thought she was happy, but now...everything will change.
We Own The Night --- by OKDeannahttp://spikeluver.com/SpuffyRealm/viewstory.php?sid=35108Summary: Canon, Post Series Buffy Summers hated lying, but sometimes a girl had to do what a girl had to do and this, unfortunately, was one of those times. Because if she told Spike the truth, he'd likely think her insane, but if she lied, if she said she was happy for him when she wasn't, maybe he'd come to realize what she'd only just begun to learn.
When you love someone, you do whatever it takes to get them back, even if it means telling them a little white lie to make it happen...
My Life Closed Twice---- by Anaross http://www.athenewolfe.com/justrewards/viewstory.php?action=printable&textsize=0&sid= 577&chapter=allSummary: Post-Not Fade Away. Buffy seeks Spike's remains, but then finds him in the most unusal place. Spike/Other, Spike/Buffy.
A Stone's Throw from Yesterday ---- by Eurydicehttp://dark-solace.org/elysian/viewstory.php?sid=435Summary: Fall, 2006. The Sunnydale Hellmouth has been destroyed for over three years, and the Scooby gang has scattered to the four corners of the globe, continuing their fight against the dark evils of the world. In the Egyptian desert, a single man hears a tortured plea for help. It's just a shame he doesn't recognize his own voice...- Complete.
Distance --- by Herself http://www.echonyc.com/~stax/Buffy/herself/distance.htmlSummary: When Buffy goes to the aid of an amnesiac Spike after the L.A. apocalypse, they both find out what lies at the core of their mutual attraction. Can their new love survive the return of Spike's real memories of all that's gone before?
Secrets and Lies--- by angelic_amyhttp://dark-solace.org/elysian/viewstory.php?sid=5A world away from the Hellmouth, Buffy is moving on with her life. When a case brings her to LA she discovers something that had previously existed only in her dreams. Will she get the chance to voice her unheard thoughts before it's too late? Set in Season 5 of the Angel timeline, during the episode 'Damage'
Never Alone ---by Lilachighhttp://spikeluver.com/SpuffyRealm/viewstory.php?sid=7374Summary: Buffy flies to America when Spike vanishes during the LA battle. She tracks him to where Sunnydale is being rebuilt But Spike doesn't remember her and there is a brand new threat arising. Can she forge a new relationship without destroying them both?