I am so sorry! My fiance committed suicide when I was pregnant and it is not an easy thing to deal with.
When Azelin was four she started asking questions and I simply told her father died. I did not elaborate. When this was no longer enough I said he died of gun shot wound. When that was not enough I explained that Jeremy was very sick (which anyone who does this is) and no longer could think clearly and shot himself. In this way I did not overburden her with more information than she could handle. I expressly forbid outsiders to discuss his death with her until she was much older. They could discuss grief, but not his actual death.
I am not sure of your faith background, but I started discussing with Azelin that God does not withhold his loving kindness from the sick. If he was to sick to think then God would forgive his actions. I started this long before it was an issue, but there are many who believe suicide is unforgiveable and wanted to address with her indirectly the stupidity of that. None of us are aware of all of our sins and thus none of us have repented from all of them.
Survivors of Suicide is an excellent resoure. The website is www.survivorsofsuicide.com
I am not sure where you are located, but there are grief groups for children in almost all major cities.
Troy Timmons is an excellent counselor also and he does accept Medicaid, if you are in the Amarillo area.