Mandie: I don't hate him any longer actually, I just feel pity for him. Yet I am a responsible person and do not want another human being to be suffering like this.
I know something of what you're feeling right now, as my father is an alcoholic, has dementia and was never an affectionate man towards the family (though he was never physically violent towards any of us). In a situation like this you can't help feeling that the person has brought many of their problems upon themselves, as it is known that alcohol can cause/contribute towards dementia. However, when the awful combination of alcoholism and dementia takes effect on a person it is pitiful to watch and you can't help but feel concern for a frail elderly parent, no matter how badly they've behaved in the past.
You've been offered some great advice about contacting social services etc, so I will just try to offer some support on the emotional side of things. Firstly, no matter what anybody else may say or think, or how social services may try to cajole your family into taking some active part to help your father, YOUR OWE YOUR FATHER NOTHING. Stand firm, be resolute and point out that whilst the local authority has a legal duty of care towards your father, you have no such legal burden on you and nor are you morally bound to provide care for a person who treated you all so badly in the past. It's a horrid situation, absolutely vile, but it sounds as though all your father's chickens have come home to roost, which seems to be nobody's fault but his own. So, DO NOT GET DRAWN IN by social services.
I would try to minimise the fire risks, for the sake of the neighbours as much as anything, but not get directly involved in any other aspects of this situation. Is the house detached? If not, it might be wise to inform the owners/tenants of any adjoining property, so that they can make sure they have plenty of smoke detectors/fire alarms in place, just in case the worse happens, because it would be awful if other people got hurt. Also, if possible, it might be wise to have the cooker removed, certainly if it's gas, and you could consider installing fire/smoke detectors/alarms in your fathers house. You don't owe your father anything, but I'm sure you'd not want any harm to come to innocent bystanders/neighbours.