my mom was the same way with my boyfriend.

i tried working things out, and calmly explained that this is the person who i want to share my life with, and she has to accept that. But that didnt work.
i dont know what to tell you...things never really got solved with my mom and i, she just kicked me out and told my boyfriend im "his problem now"
you're an adult now and in college. You can choose who you date, you're mom just has to deal with the fact that she cant control your life anymore. Your growing on your own.