Issue with college mates 🙁

During a recent Industrial Visit (IV), my girlfriend and I sat together on the bus. While I was resting my head on her shoulder, we shared a few private moments—some kissing and cuddling. At one point, she reached out to touch me, though we tried to keep it hidden behind a bag. However, it seems my friends noticed the kissing and cuddling. ​Since then, the atmosphere has changed completely. My best friend, who I used to sit with every day, now refuses to sit near me. The entire friend group is avoiding me, and I’m left sitting alone at the back of the class. When I tried to apologize and bridge the gap, my best friend was very harsh. He told me that I wasn't raised well by my parents and claimed his upbringing was superior. This comment deeply hurt me, and now I feel completely isolated. I’m looking for advice on how to handle this