Worried about added burden w/ useless husband

I had two children when I met my husband. My youngest at the time was only a few months and not only was the pregnancy and delivery traumatic for me, but the relationship that created the baby was as well.

On our first date, I explained to my husband that I was recovering from trauma that would affect me my whole life and that I never wanted to be pregnant or have any more children. He shared with me that he always wanted two children of his own and hoped that if our relationship progressed that I would change my mind...

Flash forward two years into our marriage and he's badgered and worn me down enough to agree to give him a child of his own. An idea that would prove to be a mistake on my part.

Of course I love my youngest son, I love all of my children desperately, but children ARE a burden of responsibility and every ounce of that responsibility has fallen on ME. 😧

One of the things my husband and I have in common is our zest for life and nature and outdoor sports and activities... Having more children has completely robbed me of this part of my identity, as every activity we've taken part in since baby number three, has involved me hiking a heavy baby to a beautiful spot in nature where I sit and babysit while my husband then spends the next hour or so playing, climbing, jumping, swimming, exploring, and having fun. Once it's time to go, he'll ask me if I want to do anything quick before we leave...while he and anyone else we came with are already drying off and getting dressed. But, if I do, he'll complain 5 mins in that I should come back and get our son 😦😟

This was our entire summer last year. This year, having allowed myself to get knocked up again, I'll spend the first half of summer recovering from pregnancy and childbirth. Leaving no time to reclaim my body, strength, and/or ability to enjoy physically demanding summer activities. Not to mention now having TWO babies under two years old that require physical attention. And being across the country from anyone we know, knew, or are related to.

When I bring up to husband how unfair I feel this is to me, how I feel about being robbed of my youth and identity, how burdened and lost I feel under the weight of being no more than a pack along nanny to his escapades, the building resentment of it all... he immediately accuses me of not loving my children, then threatens to quit his career and force me to support the family so that he "can" stay home and care for the kids full time. And at some point, will generally throw in accusations of expecting me to hand his children over to Child Services someday. ☹

I'm so lost and so worried. I know that this next baby will fall completely on me as well and that he expects this to be the normal, and that my complaints are an issue and a sign of a personal problem.

When he asks "what do you want to see happen?" and I respond that I'd like him to take some responsibility, that I expect him to share the burden, it just loops the conversation back to him making accusations and threats.

I really need some help here. Don't know what to do.