Buffy's mom and stepdad Giles died, and she briefly meets William/Spike, Giles's nephew. She goes to live with her Dad, and evil Stepmom and Stepsister who all emotionally abuse her til she decides to leave. She runs away to Spike in I think Las Vegas? He takes her in and they fall in love.
Any help on finding this fic I've suddenly remembered would be much appreciated! Thank You Very Much!!☺️

Take Care, Amber

Hi,
It could be The Trouble With Keeping Promises by Jaesha and on EF. It's unfinished though. 😢
Found it on this topic.

Summary: After losing her mother and stepfather in a horrible accident, Buffy Summers is sent to her cruel and uncaring father in Los Angeles. When she finally gets the courage to run away from her abusive home life, she banks her entire future on a chance encounter from years before. Spike had broken his promise to keep his uncle's stepdaughter safe, but now that Buffy was suddenly back in his life he had a chance to make it right again.

Yes! That's it!! 🙌 Thank You SO Much!!! I tried looking for it on here but didn't see it in that topic (I searched for Buffy running away), and couldn't find it via summary either. Thanks again for the help!!!😁

I'm glad it was the one! 😄 We all remember different details from a story, so looking for it is always tricky. 😉
Thank you for letting us know.