Mattheo Riddle was your boyfriend of 1 year and 2 months, they were both in their 7th and final year at Hogwarts when Mattheo's ex-girlfriend (Pansy) got so jealous she decided she wanted to ruin you.

She came to Mattheo andyou while you were sat snuggled up on the common room couch together and started screaming about how you had cheated on Mattheo last night, waving her phone around with pictures of you and a boy together in bed.