Not sure where its headed...

So ive been married for 4 yrs now and my SO is 8yrs older than me. He has put a time limit in having kids as that he wont have kids after 40. He will be 39 in September and we have 0 kids! Our marriage is not the greatest, we never have sex and have done counseling a few times...just to fall back into the same issues. Hes is alwats stressed out and i do everything i know to do to help him but it seems to never be enough. We have talked about divorce a few times before but im at the point i just want to give up! I feel like im being cheated out of the life i have always wanted! Amy thoughts or words of wisdom?