Colditz I think I do understand some of the pressure you and DP are going through with your working. DP and I both work shifts and this month we have one day off with each other. Possibly two if he delays leaving for a day (which I think he will actually). On that one day we plan to do carpet cleaning.
What I am trying to say is living your life like this isn't easy. DP and I seem to muddle along, but our relationship definately does suffer. We haven't been out together since the start of Sept and are a young couple. We have no spare cash to go out for a nice lunch somewhere anymore. We dash to the food shopping between night shifts.
ATM, our life stands to change in a few months as we are relocating and plan to use a childminder for two of my shifts a week. In a 3 month period that will give us 5 proper days off with each other. So I am just getting through it. But TBH, I don't feel close to DP. One of us is always tired or snappy, if not both of us. We argue and get at each other, quite a bit tbh.
We also have substantial debt problems but relocating should be a fresh start for the both of us and I hope that we will resolve them.
However, DP is not, fundamentally a nasty bloke. In many ways your DP sounds as though he could be. And although I am not trying to excuse his behaviour, I wonder how much of this is down to the pressure of your busy lives? You are both working full time aren't you? I was going to suggest trying to find ways to finance childcare, but of course you are shortly to have another.
Has your DP expressed any wish to change with regards to his spending and blatant disregard for his families security? DP has mountains of debt, but at this stage he would never let it be so he could not afford the rent. That smacks of someone who is totally unprepared to have a family tbh.
I seem to have gone round in complete circles here. What I am trying to say is that some allowance should be made for moods and snapping with the pressures your lifestyle brings. But there is no excuse for blowing all the families cash down the bookies or whatever. I can't see that you are going to make this man a good un.