Hi Stiv2us,
I have been diagnosed with T2 for 11 years now, and i have had bouts of depression, leading me into some dark places in my mind, where i too thought of ending it, but the thought of leaving my wife behind stopped me.
Unlike you, my kids are all grown up, but i have grandkids, aged between 9 years and 4 days. Each one knows that i am diabetic and that i have to inject and take lots of tablets, my 4 year old grandson is made up, because hecan come to me to open his sweets knowing i can't nick any.
I hope you take to heart some of the advice you have recieved on site, and seek professional help, but talking to your wife will also help alleviate some of your problems. Failing that, post some things on site about stuff you like to do, books you read, tell us some jokes, anything to occupy your mind, and get some interaction going.
The help and support is out there
Take care,