I have a user class with a many-to-one association to itself. This allows a user to have a "best-friend" association to another user. However, if userA is associated to userB and userB to userA this causes somewhat of an infinite loop. Even if its userA -> userB -> userC -userA, this can always loop. Lazy loading would fix this, but there isn't lazy loading for many-to-one.

What should I do in this situation?

Hibernate will not loop in this case, since it detects cycles.
Check that you equals hashCode is prperly implemented.

Lasy loading of many-to-one is achieved using lazy='true' in the one side (<class lazy="true">)