Your siblings partner

You're a 21 year old female or male. You haven't been in a relationship at all because well...ever since high school you had a crush on someone. but that all changed when your sibling decided to snatch them up. they've been dating for 7 years but they've had continuous problems in their relationship, and it involves you. Your siblings partner keeps stealing glancing to you from across the room! so what do you do? give in and ruin your relationship with your sibling? or refuse and ruin your reputation with a person you've liked forever? Note: Guys its been like 20 days but i actually lost motivation...my stories are FLOPPING. Any errors? please lmk...dont let me look stupid 😭