It just might be his character as many people, including my own father, are pessimist. He is the father, the man and the breadwinner of the family. You can see how much of responsibility is on his shoulders. Besides, he cares for his family and has to plan things in his mind all the time for his family's comfort. You can see doing all of them at the same time can be really overwhelming, leading someone to be strict and stressed.
I agree though. Have a talk with him and tell him you appreciate his effort but remind him that you and your mother need him healthy, so he has to reduce the amount of stress and maybe give himself a vacation.
But still I disagree with not using magick as an aid to our normal daily life. Magick is there to help us and why not use it when we can? I don't mean as the main action but as an additional help to our main action. For example in this case, one could cast a spell to calm the daddy's stressful thoughts and bring him peace. Why not sending him positive energy when you could?
As another example, think of cooking. Onion is not the main food but it can add delicacy to it. It's just a tool to help, just as magick is.