Wife threatens for suicide

Respected Sir/ Mam, Not sure how to explain and open up about my problem so I had to read queries sent by many people and here I'm trying to explain the current situation. We've been married since 2012 (been 12+ years now) and are parents of two kids (a 10 y/o daughter and 4 y/o son) and living in NCR (and her parents lives in Prayagraj and mine in Bihar). Our marriage was purely a love marriage where none of our parents were agreed, still, we did that after deciding ourselves. It was a high time for few years, then slowly our parents accepted us. If required, pointing it out that we have a huge age gap amongst us i.e., 10 years (I'm 34 and she's 44) and she's non working ever since 2013 (after expecting the first child). The problem is, my wife has a very short temper and she looses her control in every small things and starts shouting in front of kids as well. Ever since we started, I've tried to ignore this behavior and always takes a step forward to cool down the tempers to make things normal however, it happens again in few days for any reason. At every major step, my parents have helped us in buying a flat, a car and making jewelries for my wife even after that she doesn't respect them and always pin point very small things which can easily be ignored (considering they are elder and are in-laws). The current situation is, even if we talk to each other to resolve or seek any issue or advice, it immediately turns out to be a fight. From last 3-4 times, I'm noticing her having various medicines (i.e. brufen, Dolo, Montair LC, Naxdom etc) when I'm working or sleeping. I get to know this when I see various wrappers in the dustbin. She also threats me up to suicide. Not sure what to do in this situation considering the fact, we still love each other but when situation happens like this, things are totally different. Seeking your advice as to what action I can take further as I have a life to live, 2 kids to raise. Please advice.