Hi Rachel
Just because she is your mum does not mean she is not a normal person, who may be able to go out and have a couple of drinks with friends and maybe hook up with a guy she likes. You are here because you are not that person i presume and you just have to accept that she will not get it i guess?!
I personally think if you lead a sober life that you will a lot more joy than your Mum ever had, it is difficult to accept that family members will never understand what you are doing but that's just the way it is...
I am best friend with my ex gf (weird huh?!) and have close contact with her 22 year old daughter who is in University in the UK and i find it very odd that your Mum is wishing you had a BF...her daughter is stunning and the last thing i would wish for for her is to be getting dicked by the school/college popular jock?!
Anyways wishing you the best:-)