Son wants to stay home from high school tomorrow on valentines day

My son he's 17 and a senior has been begging me weeks prior to let him stay home from school on valentines day. I ask him why and he says because it's gonna make him sad (He has low self esteem and self harm issues because he thinks he's ugly and he's never had a girlfriend before because he always gets rejected or played over) His school is very strict and stupid about the attendance and I don't want tomorrow to be counted as an absence over something small.