Amateur psychology aside, I don't think there is too much evidence that his wife's death contributed to his politics particularly much. I'm sure it did in fact cause him grief, but I have a feeling there is an underlying "and therefore, he did what he did as leader of the Soviet Union" being asked in this question. To that end I would answer that no, I don't think there is a radical change in Stalin's pattern of behavior/ideology at any point.
I wrote a post several months back about the consistency of his positions (more or less), which is somewhat relevant in this case, so here is the link if you'd like to read that as well: http://www.reddit.com/r/AskHistorians/comments/1olmdl/did_stalin_introduce_harsh_repressive_policies/cct9rir
This does not directly answer your question, but to give a little insight on Stalin's personality three years before his wife died, here's a quote from Ivan's War by Catherine Merridale:
“In 1904 a group of comrades were out for a walk along a river swollen from spring rains. A calf, newborn, still doubtful on its legs, had somehow become stranded on an island in the middle of the river. One man, the Georgian Koba ripped off his shirt and swam across to the calf, He hauled himself out to stand beside it, waited for all the friends to watch, and then broke it legs.”
Stalin called himself Koba after a character in The Patricide by Alexander Kazbegi.
I first heard this on Hardcore History "Ghosts of the Ostfront," which gives a pretty interesting, albeit dramatized, portrayal of Stalin and the eastern front.