M.T.
K., I am sorry that you are feeling so unhappy. Something I've learned over the years is that happiness is a choice, and no one else is responsible for your happiness. You need to make it happen.
If you are unhappy in your marriage, counselling can work if both you and your husband come in with a clear list of things that you'd like to work on, what your priorities are, and you need to each be willing to work on those things. You can't change everything at once. Work on the things that you can control.
Why have you given up everything to be a mom? Martyring yourself doesn't make you happy or a good mom. Good moms take time for themselves. Your identity changes when you become a mother, and you need to embrace the new identity and work with it. If you feel like you gave everything up, what did you have before that you want? A job? Plenty of us work with kids. Going out with your husband? Get a sitter every so often and go to dinner or coffee. Time with friends or going to the gym or working on a hobby? Same thing, hire a sitter, swap babysitting favors with another mom, line up your husband. Don't ask him to "watch the kids for you." Why are you fully responsible for the kids? I was never fully responsible, it was never assumed that the kids were always with me and that my husband could make whatever plans he liked. You need to make your weekly plan with friends or to take a crafting class or go running or whatever it is. Don't wait for him to say, "Hey, you could use a break, I'll keep the kids for the day." You need to tell him how it is. Speak about this in your counselling sessions.
I'm not sure how every friend you had moved away, but 9 years ago, I moved here to a new area where I knew no one. It felt isolating for the first year or so. Then I met other moms at Gymboree and preschool, one mom invited me to join her book club, I met other women and made friends. This is your responsibility. If you want friends, they're out there. Go find them rather than saying you're miserable because you have no friends. If you have kids in school and other activities, you must be running into other moms a lot, especially if you're an at home mom. You need to cultivate the friendships.
Good luck to you, K.. I hope that things work out for you!