OK, most of what you have listed here is "fixable", assuming that both of you are willing to participate and do the work. Both of you need to look deep inside and decide if you want to do that. Since your husband says he still loves you, that is a good sign on his end, and since you are saddened at admitting that you feel better w/o him, that is also a good sign, IMHO. I agree with some of the others in that both of you need counseling-both separately and together-and he needs to be screened for depression just in case. Bring up the lack of hygiene with your family doctor-he'll get the ball rolling.
I also firmly believe that you need some time for yourself. I know, I hear you: "With two jobs and 4 kids, WHEN??!!" I do believe that it is possible to carve out some time for yourself. How about shifting some of the smaller chores onto your husband and older kids? The older kids should be taught to do laundry, dishes (by hand or dishwasher, whatever is appropriate), clean the kitchen, pick up stuff off the floor and put it away before they go to bed, dusting the house with those Swiffer dusters (even your little one, assuming he/she is mobile, can "help" with that one-no cleaning chemicals required!), each older child can clean a bathroom once a week, etc., maybe even learn to cook! (I'm not sure how old your kids are, so I'm just tossing out ideas-go with what's appropriate!) The bill payments can be automated with online bill pay through your bank, food shopping can be done online-look for a supermarket that offers "Shop at Home" services-you put in an order online on their website, then either they deliver it for a small fee, or you (or hubby) can pick it up on the way home from work. I know some ShopRites and Stop n Shops offer this. Diapers.com will deliver diapers and other baby stuff to the house as well. Also, check out Alice.com and Amazon.com-both offer nonperishables that can be delivered on a regular basis if you want. Do you have a crockpot? That can help, too-load it up the night before, keep it in the fridge o/n, then set it up and turn it on before you leave for work in the morning-dinner will be ready when you get home! Once you get the kids & hubby going on even some of what I've suggested, that will give you time for yourself. Find something that you like to do, even if it's just reading a novel or something-your hubby has already found his hobby: gardening. Get your nails done, or a massage. Go for a walk, whatever. Just do something that is totally for you, and DO NOT feel guilty about it. This will at least begin to ease the resentment you feel towards your hubby for his doing what he wants to do.
And here is a possibility for the hygiene problem, in addition to the medical/psych screening: get the car(s) in the back yard and make washing them a family project...then everybody attack him with the water and soap (make it fun!). He'll be clean(er), then you can get the message across to him in private (I did that because you clearly aren't doing it for yourself anymore-now I must say that you are much better. Now, what can we do about your teeth-you have some spectacular bad breath!). Send him to the dentist? Temporary, but it might help.
And, while you are obviously venting here, check out manicmommies.com. This site-and they also have a board under the Big Tent, look on manicmommies.com for sign up details-is an international group and podcast (search manic mommies on iTunes, also available from their web site) of "moms trying to do it all-and then some!" We vent, provide advice, laugh, cry, and most of all learn that we are not alone in our problems. Once a year, the moms who started it all organize a trip called "The Escape", on the first weekend of November. Moms only, no husbands or kids. Last year it was in Napa Valley, CA, this year it's in San Antonio, TX. We get together, go on excursions, take "classes" on parenting,etc. make new friends and get a break! Check it out!
Good luck and hang in there!