Does she get pin/bbm from other contacts besides you? If those work then maybe check your contact profile in her phone; maybe something got blocked, although I'm not sure what it would be.
Posted from my CrackBerry at wapforums.crackberry.com
This thread is funny to watch. Not funny in a sarcastic way just a couple of the posts and replies. Significant other. That was classic. As mentioned, really sounds like a firewall setting. Does she receive from other BBM'rs?
Well, now that does sound very unusual. Wish I could offer more but alas this seems that it will only be resolved by the people that can trace the BBM routing itself. RIM. You may need your better half to contact her carrier as well and go through their channels to be transferred to RIM too. Make sure that you or her have both PINS readily available if they ask for it. It will make things go a lot smoother.