As far as I know state pension stops being paid to the deceased when he/she, well, deceases.
Any allocation of private pensions usually goes to the person that the deceased has nominated in his/her will. Failing that, next of kin, if the pension is to continue and nobody contests it.
In any event a widow will be entitled to her own state pension based on her earnings plus a top-up called Pension Credit to bring it up to a level that has been determined is necessary to live on.
At present, if there is no other income, that level is £148.35
It may be advisable to seek legal