I'm sorry for your loss and how it has affected you. But in answer to your query, no, almost impossible. As the others have said on addiction but gaming itself, it's pure escapism. There never was a correlation between shooters (as in gaming) and shooters (perpetrators) for instance, it's just plain sense that they'd play something violent instead of peaceful. Personally, I've literally gamed at least 15-20 years of my life away, and as much as I love(d) it, one main essence is escape from reality and have yet to see a game (addiction) that could steer one towards suicide (let's forget nutters who leave their kids to starve because of World of Warcraft).
Of course, there's also gaming addiction as in gambling, and that can certainly lead to intense stress. Did sports betting over a decade ago and it went really well but also blew all of my winnings when outside factors messed up my system. It got personal, but never lost my original stake. So, while it can give one powerful highs and lows, if one gets carried away and perhaps into financial trouble or otherwise under pressure, hm, that might indeed lead to depression and suicide.
But I take it we are talking the first type of gaming?