Completely burnt out how

How do you cope with burn out? I’m a stay at home mom of 2 one with ADHD and one to young to be dignosed but showing all the signs and my husband has it as well. I am completely burn out! All day long I’m cleaning up messes or breaking up fights and both of my kids need help falling asleep (patting their backs) so that takes another hour of my day and My husband works 11 hour days and weekends so I never have time alone. I do nothing for myself and I’m completely and utterly burnt out, and then when I try to sleep I can’t cause it feels like my heart is racing. I’m so tired and I just don’t know how to cope. I feel like I’m only here to serve others and I just want to give up.