Is there any hope?

Ok so this is my first entry. I so need to vent.  I'm a 24 year old woman and I always knew something was "wrong" with my husband of 4 years but I couldnt quite put my finger on it. He knew he had adhd and so did his mother but no one told me until i discovered it on my own. Now 4 years later I finallly know why he wont consistently keep a job, never remembers appointments or plans he's previously made, waits until everything becomes an emergency before he half way does anything about it, cant focus long enough to complete anything, and never takes initiative to help with anything like cleaning, spending time with our 2 children (boy 5, girl 2), fixing household problems, etc.

My husband would always blame his irritibility and anger issues on him having type 1 diabetes and his sugar being too high. This could be managed if he took care of himself properly. But because of the adhd, he cant focus and function properly so he winds up never checking his sugar and never watching what he is eating. He thinks all he needs to do is take his shot and nothing more. Adhd is the root to all of his problems. Its like a comorbidity(one or more mental illnesses stemming from one). He walks around angry at the world because of his failure and I'm so tired of being the punching bag. I try to suggest counseling and and maybe even medication, but he wont put any effort into trying. He doesnt want to believe that his disorder is why our marriage is failing and our lives are falling apart. Sometimes....well most of the time i just want to give up, walk away, and start my life over. But then i feel like i should try to help him so that our family can stay together, but if he wont put forth any effort to get better, what is there left for me to do? I can do all the research in the world but if he refuses to even glance in the direction of seriously getting help, there is no hope.  I'm all for couples staying together and working through the hard times, but when there is only one spouse doing all the work and pulling all of the weight, that's when i believe it's time to pull the plug. Am I supposed to just waste all of my youth crying, fighting, and struggling with him? Are my kids supposed to suffer the neglect and mistreatment because he is too irritated and grumpy to deal with them? I'm so tired. Literally. This stress has taken a tremendous toll on my health. And to top things offf, I'm pregnant with my third child and scared to death to do this alone. But it's killing me and now I'm suffering from depression.