ADVICE PLEASE

so I'm 16 and I came out to my cousin about 3 years ago which was great and I've dated 3 girls but kept each one a secret. lately I've been dating boys bc my friends were starting to wonder why I was still single... but now I've been dating this guy for a solid 2 months and he just told me he loved me and I can't say it back bc I'm not into boys at all. I feel bad for him but I know if I tell him I'm gay everyone will find out and idk if I'm read for that. I also wanna tell this girl that I'm hella into her but I don't wanna mess up our friendship. I just need some advice and someone to talk to who's already come out to there friends and family.