A rose by any other variety of its name?

A coworker just called me "Al!" and then added "-yson" because he didn't know if he could call me that.
I introduced myself as Alyson at work because that's what everyone was calling me before I got here because of my CV.
When I started med school I decided just to introduce myself as Aly to everyone because a lot of people end up calling me that anyway and at least it would be homogeneous then.  But now Mindy's at Jeff and she calls me Alyson so that mixes everyone up, but it would be weird to me if she called me anything else.
I never introduce myself as Al, but it works.  My sister calls me that much of the time and Lisa called me that through most of high school.  I also had a friend in the 6th grade named Maxxzina (a teacher asked her if her parents were playing Scrabble when they named her) who called me Al out of the blue.
I think of myself as Alyson, I think because that's what my mom calls me (when she's not calling me Gee, Scooch, or any of a variety of other nonsense words).
So Glen starts work in the office tomorrow and it takes a lot of work for him to not refer to me as Aly, so we'll have to see how the distribution changes over the next few weeks.