It's a process and yea, of course you are going to be a little off. You will right yourself up.
I was also living in the home when this happened. I'm sorry, but, I dont think he should be able to just come over. I dont care if its his house too. Its your home that you are living in and unless he doesnt mind you showing up where he is living unannounced and making yourself at home, he should be told it isnt ok. Nor is taking anything without your permission.
"H, please call before you come over. I do not come over to where you live unannounced and expect the same from you." or however you want to say it.
Also, cleaning out the drain and stuff like that...figure out how to do that stuff yourself, ya know?
Time to start showing him that you heard him. Time to start realizing you are more than capable.