I've had those days where I've been tired of being the strong one.
It's okay to be upset, just don't let it get out of control. When I get to feeling like this, I take time and let myself feel whatever I'm feeling. If I'm sad, I mope for a while. If I'm angry, I let it out. Then I find something in my life that produces positive emotions, and indulge myself. Whether it's a comfort food or a hobby or watching a favorite TV show/movie, I allow myself that time and freedom. After all, I've worked so hard, I've had to deal with XYZ, etc. etc.. I deserve to be as happy as I make everyone else, if not happier.
Does that make sense? I feel like I'm rambling....