M.A.
As a fellow mom of 4yr old twin boys, I can honestly say I've been in your shoes. I know that with 2 small ones, who are more mobile now, that life is rough for you guys right now. You're both probably tired, and wore out from the day to day grind... which leads to short tempers and disagreements. Please try to focus on all the good things that he does for your family (which likely come from a place of love or he wouldn't do these things without being asked) and try not to bicker with him. Then focus on getting a break from the kids... even a few hours away to relax or get a pedicure or spend the afternoon with a friend, something... so that you can have the energy to be a positive, loving partner to your husband. Once, you've tried that, then the two of you probably need some alone time also, away from the kids. I know that this may be easier said than done... my husband and I have no family closer than 300miles away, and were relatively new to our area so didn't know many folks in the beginning. I do agree that marriages and intimacy have ebbs and flows, and that this period too shall pass. As long as you and your husband don't do or say things that can't be undone, and continue to work at it, then you too can get through this.
My other recommendation would be to talk with your ob/gyn or primary care md and discuss the possibility that you may be going through some depression. They can recommend some counseling possibly and also discuss with you other options. If your husband is willing, then see a counselor together, that way you both have a chance to get things off your chest... you may realize that your both feeling the same way, tired, overwhelmed at times, but still in love with the other person and wanting it to work.
I am new to this site, but if I can be of any help, please let me know.
Hang in there... I truly believe that God blesses those that can handle the challenge of twins, so he has faith in you too.