Well... if she murdered him, she has departed a long way from her professed faith and belief system. A very long way, maybe it was instantaneous, or maybe it was a long time coming, but to my knowledge , there is no religion that sanctifies killing one's husband.. on the other hand, there are lots of religions that are ok with dragging one's wife around etc..
Maybe there was some outrageous provocation, let's hope there was, for her sake.. 30 years in an Angolan prison would be hard, hard times.. especially with no family there to bring in food and medicine, clothing, etc... sometimes these things are not forthcoming with regularity in prisons elsewhere...
It would be handy to know how she killed him, perhaps,, that might explain things a bit more, make things a bit clearer, although, even at this early stage, there seems to be no nod to it being an unfortunate accident, according to authorities....