Op I would have been horrified if my mum had said this to me lol
Having said that, I do feel for you,it's sounds like you're not prepared for him to be flying the nest.
This is the time at which you switch your parenting to style to one of benign neglect 
He also needs to learn to cater and care for himself for hereon in...Otherwise he'll grow into one of those men so oft complained about by women who find all the domestic work is left to them 
I know someone who's mother still made him a packed lunch every day following his masters, did all ironing, visited weekly to clean his flat...Seriously, its been a nightmare for this persons now wife!
Since you likecto be needed, and I appreciate that, perhaps you can find a volunteer role to keep you busy somewhere you'll be well valued, especially during the transition?
He might well live like a slob during uni (although some become strangely houseproud) but he'll get over it in time and he will love knowing that he can always come home to you when he needs you. It's a tricky transition, but you'll embark on a wonderful new phase of your mother/son relationship.