I am so very sorry for your loss.
My DH took his own life nearly two years ago now, my daughter was 2 at the time. I felt shock, sadness, disbelief and all consuming guilt - I had told my DH a few days before that I wanted to separate from him, he had an addiction that I couldn't cope with.
Please know it was not your fault.
SOBs have a helpline and meetings for when you are further down the line. I belong to WAY which has a separate section if you are bereaved by suicide and meet ups, this really helps to know you are not alone.
I waited a couple of days to tell my two year old dd as my mind was so jumbled and I was so in shock at the time. I just told her that I had something very sad to tell her, that her Daddy had died and a v v simple explanation of what this meant.
You have so much to cope with right now. I hope you have some support from friends and family. Lean on people as much as you can.
I found a great counsellor and this helped me massively.
I am so very sorry. It's really heartbreaking for you but please know you are not alone and you can survive this.