I feel a bit sorry for Will, because he is grieving, and trying to work full time and run a household, and having to chart unknown waters in parenting a teenage girl ...
But none of that changes the facts that:
a) he is a prize knob, very unpleasant, and just generally not a nice person
b) he is consistently pushing away any offers of help, and
c) the children shouldn't suffer because of his inability to cope. All of those kids, including Poppy, need to be taken out of his care and looked after by someone who can actually see to their needs. Leave him alone to sort his issues out and wallow in his misery, but don't make the kids suffer.
Also, I agree with pp that Andrew was always depicted as a distant and, frankly, crap father. Wasn't he borderline abusive with Nic? He's clearly been rewritten to fit the current storyline.