Something doesn't ring right here.
If you have been reading with her since 2012, it seems very strange that she just blocks you... I know some readers on Keen have had issues with the system blocking callers randomly, and they can only resolve it if they notice..
I doubt Customer Service at Keen will help much, but it might be worth asking them if they have any glitches in the system..
I don't suppose you have another contact for her, or know if she reads elsewhere, so you can ask directly what the issue is?
I think good readers recognise they have a responsibility to regular callers - i.e. it is a relationship to some extent and requires trust and respect..
I've never had a "go to" reader block me.. I really wonder if this is an error..