Welcome to the forum!
I'm glad you are finding your work situation manageable. It sounds as though you do have lots of pent up frustration that gets released once you are at home, which you have recognized. Coping strategies are great tools to have. Before you get home, you could park one street away and just sit listening to music in your car for maybe 10 mins. Once you walk in the door, you could say a quick hello to your family, and then go in a room and just relax by yourself for a while, to unwind from the day. If you feel that you need space when you first get home from work, letting your family know this is important. So long as you say this calmly and respectfully, their response shouldn't be negative. Saying something like "I find myself feeling tired and frustrated when I get home from work, so from now on I think I need to just be by myself for a little while to unwind from the day." This is honest and to-the-point, and it doesn't accuse anyone of being a part of the issue.
Here are some sites that may also be of interest:
If you feel that your mental health is at risk, going to your doctor (GP) is a good idea. You can also call Beyondblue's 24/7 helpline for any emotional or behavioural issues you need help with, or for general advice: 1300 22 4636.
I hope something I've said has been helpful 🙂