I have 2 tricks for when my a$$ is grabbed )depending on my level of intoxication.) These were used in my college days and I am now much more respectable (well that's what my employers think!!) ) 1. Grab hand that is grabbing you,while still looking away dig nails in and stamp preferably stilettoed foot on foot of person who owns hand. This is an unnoticeable to the crowd as what he did to you
2. Do exactly what you did! Oh yes, I have done this a few times.
A friend of mine has a couple of lines she uses ranging from "in your dreams" to "shouldn't touch what you'll NEVER have"
I have done the feminist rants too and asked guys if they thought that grabbing my a@@ would make them more attractive to me, and proceeding to slurringly lecture them on how to treat a lady!
I was boyfriendless at 19 too, its a good thing, If I had met my BF earlier I couldn't have been as sure about him and my feelings for him unless I had something to compare them to! (we got together when i was 20, in 3rd year in college)
I am pretty loved up at the moment, me and my guy are together a LONG time and understand each other, we rarely argue and work well together, we are both very independent and not threatened or insecure in our relationship. Oh and I fancy the pants of him which helps!
It just works and that's great, but I know if I had thought at 20 that I was looking for a guy to buy a house with and spend my life with I wouldn't have known where to look and would have been COMPLETELY freaked out, it just happened that we did meet when we did and we managed to stay together and its all working out great.