This is a stinker

I've just finished watching this 3 part series, & I'm so disappointed with the stupid story plotting.
It seems like the whole thing happens over the period of a month, these people seem to be 2 dimensional.
Sheridan Smith's character doesn't seem to grieve for the person she was in a relationship for over 3 years (they were married for 3 years so I guess they were in a relationship before that). She doesn't frown throughout although supposedly angry/sad/frustrated/grief struck.
The kids seem completely unaffected by the murder of their dad.
The Police force doesn't seem to have different departments, or any sort of rules regarding allowing the bereaved spouse into crime scenes & investigations.
It really seems like such a waste of money, talent, time & that is 3 hours I'll quickly forget.