As a general rule, you shouldn't date anyone directly involved in your child's education. So even though he's a school counselor instead of a sports coach or math teacher, you'd be entering some very dangerous and awkward territory by doing any more than casual flirting.
Also, I'd like you to consider what kind of impact it would have on your daughter. Imagine her coming home from a friend's house to see her mom and her school counselor abruptly stop snuggling on the couch. Imagine what kind of questions she'll have to answer at school if other parents see you and the counselor out at dinner somewhere.
Dating within a child's school blurs a lot of lines and creates more drama than the relationship is worth. So keep having the crush if you can't talk yourself out of it, but acting on it is going to be very bad for everyone involved.