It's not long and dramatic, hon. And you are not alone. Given the details, it sounds like you are at a healthy weight and that you are also fit. You've made time to work out even with little ones, and that is great. Plus you have a loving, supportive husband.
But none of that matters if your self-perception is out of whack. Have you considered going to counseling? It doesn't mean there's anything wrong with you, but a counselor might be able to help you figure out the root of this message running through your head, and if you can find the source, you can stop it. I was never thin as a kid or young woman, and I'm more fit now than I ever was as a child, but I was the "chunky" one in my family--and even today my extended family is far too weight conscious. I only went to counseling for a few months (after the birth of my daughter), but I figured out pretty quickly how the tape playing in my head had been created.
Another suggestion would be to find other mothers--not just online, but in local play groups. For me, just knowing I wasn't the only one struggling through something helped. An activity group might help to--and I don't mean exercise, but a group that does something you love, whether a craft, or a sport, or writing, scrapbooking, whatever.
I wish I could hug you from here. Just know that you are not alone, and all that is left is for you to love yourself, take time for yourself--not just to exercise or self improve, but to do the things that you love, something to feed your soul. Good luck.