YA book I read in the late 80s Found

[jashme2004]

I'm looking for a book that I read in the late 80s, maybe very early 90s, I don't remember much about the plot but I know it was about 3 or 4 friends and I'm pretty sure it was a coming of age story. In the beginning one of the main characters had her room professionally painted purple and she put up posters with tape and her mom was mad because the paint came off with the tape and the painters had to come back to fix it. She also had a poster of someone famous(in her world)that she had a secret name for, Benjamin Moore, and she made the joke that she knew it was a paint name but she loved the name. I want to say that the cover was a picture of the 3 or 4 girls and it was yellow. I also feel like that title was something like friends forever, that's what friends are for or something along those lines. Thanks.

Update Book found...Just as Long as We're together by Judy Blume