So, that's quite a family and that would have kept you both busy- now it will be quiet and thinking time becomes grief time. I know too well the point that you are at.
So, back in 1996 I also had a failed attempt at my own life and one week later left my wife and two young kids. That alone period for 3 months or so was a terrible time. Then it all changed overnight. In the country town I relocated to I lived in my 11ft caravan. I noticed and conversed with- several single dads also estranged from their wives but many had been there many years. I didn't like the prospect of becoming a permanent resident of that caravan park.
I walked lot and one night spotted a vacant block of land in a small town nearby. I got it at auction. From then on I didn't have time to think about the past and dwell away. clearing the land, billy for tea, then relocating my garage as part of my settlement, then erecting a kit home with the help of a builder for 10 days then all by myself I finished it.
I learned a valuable lesson- distraction and hard work leaves the grief behind. Also over time another lesson- time heals then life goes on usually better than ever before. Two years ago I walked my daughter down the aisle. I'd told her once of my attempt on my life. As we got set to enter the church she said "thanks for making sure you got here dad", then I recalled my last words to myself before I left the family home some 21 years earlier "better to be a part time dad than no dad at all".
So I commend you for seeking help now to safeguard your life and well being. You are putting your family first and you are very much valued by them. Children are resilient so they will adapt. This time now is for you, to get to know yourself better and appreciate yourself.
I have selected several threads I think you will benefit from. Just read the first post of each-
There is also an organization called DIDS- dads in distress that has been going for about 20 years or so.