Should I Attend My College Farewell Despite the Sinful Environment?

Post: Assalamu Alaikum wa Rahmatullah, I’m a student and our college farewell is coming up. I’m conflicted about attending for the following reasons: 1. The people in my class are mostly involved in backbiting and slander — I feel morally out of place. 2. I recently ended a haram relationship with a girl who will be there. I fear falling back into sin if I see her. 3. The event includes music, dancing, and free mixing. Girls dress inappropriately, and many friends talk indecently about them. I don’t want to be part of such a gathering. 4. I feel no benefit in attending and believe I will regret it. However, I know some friends might mock or feel bad if I don’t show up. My concern: Am I right Islamically to skip this event, even if others don’t like it? Please advise with Qur'an, Hadith, or scholarly opinion.