Oh @Purple100, that's a lovely update to read! It's good that you're communicating about how you feel, and looking at why you do. It's great that DH has responded positively to your discussion, and I'm sure he'll be supportive that you're taking steps to address things on your side as well.
These are the tough times with 2 small ones and if you can support each other & be a team to prop up the ups & downs now, you'll be so much stronger for it as a family unit over the next 10 years!
12 years on from your situation, my DH will sometimes phone during the day & I'll think 'what was that for' 😆 But I'm PT WFH and he knows I don't always get enough human interaction in my day, and if he's got 5 minutes, sometimes he'll just, call!
It's partly a hangover from your stage, when he'd check whether I'd managed to get out the house, or see other humans - and also gauge how much of a shit-fight or otherwise he'd be returning to in the evening ;)
You don't necessarily want to create a prop, or a requirement that you speak throughout his working day forever, but it can be a godsend of support right now, especially on the tricky days.
Keep going with your new groups & hopefully you can build a little network of other parents you chime with, to knit a bit more daytime human contact & support around you.
I remember reading a book once called something like "Why Men Don't Listen & Women Can't Read Maps" which isn't anything like as sexist as its intentionally provocative title suggests ;) But it goes into evolutionary history a bit, and why on average women tend to/need to use more spoken words in a day by something like 4000 compared to men. We'd joke about this sometimes when he's come home mentally exhausted after too many meetings & being about 5000 words 'over spoken' and I'd have about 11,000 still to get out after perhaps barely opening the door to a postman & maybe saying 10 words at a checkout in a shop. It can create a real friction point in the evenings, as well as during long, lonely days with 2 tinies, so it's good to acknowledge it & keep it lighthearted if you can!
I feel for you, as the weather has been about as crap as it was during my first maternity leave, which makes it harder/so much less appealing to get out. But even going to a playground, you're likely to end up chatting to some other random parent pushing swings, even if you don't have a pre-arranged plan to see friends of your own. If you're up to it, stick a couple of old towels in the pushchair, put kids into puddle suits & just go. (personal learning point worth sharing - don't put them right at the top of a big slide in a rain suit without drying it first, the combination means they accelerate to about Mach 3 and they might shoot straight through your legs and bump out 2 metres away at the bottom 🤦♀️ still, it will be a conversation starter with anyone else braving the rain about what a health & safety conscious parent you are 😘)
Hang in there & keep figuring out wats to get your word count up, you've got this!