Telling parents about new boyfriend???

Erin

So I've been dating this guy who is 10 years older than me. I am 21 and he is 31. We work together and we've been dating for a few months now and it's getting a little serious. He told me that he told his parents about me, so I've been thinking about what mine would say if they found out. I talk to my mom about my sister's bf and she does not like the fact that she's dating him right now and I feel like me telling them would upset my mother a lot. Especially with the age difference... Not sure what I should do and if I should keep not sharing with them.