Difficulty Keeping On Budget

My frustration level with my husband is at an all time high.  It's very difficult being the only adult that watches the budget.  I know that I'm not perfect and I buy things that I don't need (hello Diet Coke) but I feel like I'm the only person taking our debt reduction plan seriously.  I've tried to have conversations with him but they never get very far.  He's onboard as long as he doesn't have to be deprived of what he wants.  For example, he wanted to go to a local consignment shop that sells brand name clothing.  He ended up finding a pair of practically brand new tennis shoes and decided that they were something he needed.  He needed them because he didn't have any casual tennis shoes and they were only $20.  Forget that he has at least three other pairs of tennis shoes and will shortly need to replace his work shoes that are wearing out.  Was there $20 in the checking account to pay for these shoes? Yes.  So what's the problem?  Well you need work shoes and the $20 you spent on tennis shoes could've helped pay for the work shoes that you actually needed, not shoes that you want. This only leaves me more frustrated because I feel like I need to make up for his budget shortfalls by scrimping on things that my son and I need.  I'm so tired of putting myself in second place when it comes to finances.