Everyone experiences anger; it's a regular, common emotion. When you are hurt, disappointed, or frustrated, anger is a way to let yourself know so you can do something about whatever is blocking your way forward. If you do not do anything, suppress the anger or feel helpless to do anything about whatever the problem is, you will get depressed.

I like when I get weird-to-me anger thoughts like you describe above; because they seem so unlike me, it makes me stop immediately and examine what is actually happening in my life; where I am feeling helpless or hurt. I still remember how shocked I was when my therapist talked about a vacation she was going on in a few weeks and I was fine with that, noted the dates on my calendar, etc. but when I left the office, I saw her car and had the urge to slash her tires It is not anything I would ever do (or even think of doing :-) but then I realized just how unhappy I was that my T was going away. I might not have learned and confronted my true feelings if I hadn't had the angry thoughts I did.