He hasn't done anything wrong except tell me he's not happy.
But he hasn't said, "I'm unhappy with XYZ, please can we work on these things." (Or has he and you haven't said?) I thought he had just announced he was unhappy, "checked out" (your words), moved out and barely saw the kids.
I don't really think he should be "feeling the consequences" of just being honest about his feelings.
Noooo, I agree. But he could feel the consequences of leaving the marriage, couldn't he? He's using his time to weigh up his options, isn't he? To decide what he wants. Or has he suggested counselling, or any other actual tangible practical steps to fix things?
If a woman was on here saying she had told her DH she was unhappy and he then booted her out of the house
Did you boot him out?
and said she couldn't have easy access to the children
We're all suggesting you get clear childcare arrangements in place! Not the current "he sees the children some weekends" easy-breezy non-plans you have now (which unfairly put all the responsibility on you).
Yes, I want to make a grand "well fuck off then" statement
You don't have to do a grand statement. But also, you do NOT have to let him disappear to naval-gaze about his unhappiness while you look after his house and his children unsupported. It's unfair.
If he's unhappy, what steps is he taking to get happy? To isolate the issues? To seek help? Is he taking anti-depressants, seeing a counsellor, starting an exercise regime, seeing a therapist?
but I just can't see how that will make things in any way better for the children later on?!
To be fair, it's not great for the kids as it is now, is it? I might he bring unfair but it's hard to know as you haven't said how often your DH is seeing the kids.
Or us as future co-parents?
I really don't think your calling him to account at this moment will affect any future co-parenting between you. Except positively, it might make him think twice about messing you around.
OP, there is kindness and generosity, and then there is walking on eggshells.