It's probably:
Family, Blood, and Prophecy ----- by iceminkhttp://spikeluver.com/SpuffyRealm/viewstory.php?sid=5390&warning=NC-17Summary: WIP Seasons 1 & 2 of Buffy. Instead of Angelus, it's Spike who the gypsies cursed with a soul. Now he's been sent to Sunnydale because of a prophecy, which he intends to stop.
OR
Bloody Soul --- by Kallysten http://www.nocturnal-light.net/fanfiction/story/103/Bloody_SoulSummary: Story goes AU at the end of Becoming 2. Rewrite of season 3. Buffy/Angel for part of the story, spuffy undertones throughout.
but this one is a good one too:
VICTIMS OF FATE --- by: Ya_lublyu_tebyahttp://spikeluver.com/SpuffyRealm/viewstory.php?sid=31210Summary: Goes AU during 'Becoming'. The soul restoration spell has further-reaching consequences than anyone could have predicted, changing Buffy's life forever. And when her life begins to fall apart around her, she finds understanding in the last place she would have looked. ~