My dad just died please advise?

my dad died 5 weeks ago and i can't believe he has gone. It was very quick for him and pain free as he was in a drug induced coma. I was so scared to go and see him when he was first admitted in to hospital as he was hooked up to loads of machines and has a face mask on and I selfishly stayed away because I new I would cry if I saw him, then suddenly 4 days after he had been admitted I had a need to go and see him. so hubby drove me there and I talked to him as much as I could as he was waring an oxygen mask that covered most of his face it was hard for him to talk back. he looked very well and was quite at ease considering all the machines he was hooked up to when our time was up I just touched his hand and told him to get better I couldn't look him in the eye as we left I told him I would see him soon, that night I got a call from mum telling me the Dr's were going to put him in a drug induced coma after that it all went down hill and a few days later we agreed to switch the machines off as his body wasn't healing and other organs were starting to fail. my family and I were there as he ped away I was even holding his hand and looking at his face as it happened I thought after the funeral I would feel soom closure but I don't I can't concentrate on anything my moods are swinging in all directions and if I haven;t got anything to keep my mind occupied I find myself dwelling and getting upset. my 3 year old son in always going on about how granddad Jeff has died and I have to put on a brave face for him and my other son. I am not sure how long I can keep this up. I want my Daddy back and it hurts like hell to know it never going to happen what can I do to help the pain