What's the Name of That Book??? discussion

I read this book in probably 4th grade (2018-19 ish?) and I’ve been yearning to find it for years now. The genres I believe was fiction, and the book I believe was probably too mature for me to be reading at the time and might’ve been an accidental slip in our classroom library. It was young- adult fs but just too grown for a 8 yr old to be reading.. anyway.. I know the book started talking abt a girl Anne marie and it’s very vague so not a whole lot of details but I think the book had somewhat mature actions… and I know at some point in the book she ran off with her boyfriend or a guy on a motorcycle to san fransissco or Diego. I know she also had a best friend along with her at some time. It could’ve been an RL STINE fear street book because I was really into him at the time and too mature for the goosebumps. I found a book that I read in 4th grade a few years ago by searching and searching as much as I knew (I had a lot more detail to that one) but I really want hope to find it. It was truly an amazing book that I wish to read again as a sophomore in high school