Thank you for reading this and helping me find this story. I only remember some tidbits.

Santana and Quinn are dating and probably living under the same roof (I think Quinn's mom/Judy is a prominent character).

Quinn has been spending a lot of time with Puck as they are given the chance to be around Beth (Shelby allows it).

During a moment in Glee, Puck and Quinn embrace and Santana lashes out on a wall. She ends up at Tina's.

Quinn goes to Tina's place and apologizes to Santana with Breadstix.