Hi packedwig
First a warm welcome to PC. It is nice to meet you. I really believe that it is the depression talking. Do you take any medications? I also have depression and when it takes hold, bad thoughts almost always come. I see a therapist (T) and he helps me to change my negative thoughts. It is important to not act on any of these bad thoughts. You say you are stubborn and I can be as well. I have to make sure that I turn that stubbornness toward good goals because I can be so determined. You can use your determination in a good way if you knew how to point it in the right direction. Do you have a (T)? I really feel that talking to someone in real life (not just here) about how you feel would be beneficial. We also want to hear about you here.
You asked for suggestions. I do have a few things that help me.
1) I read books on meditation. (It helps to keep me in the moment and not let my bad thoughts take over.)
2) I read books by Melody Beattie (codependency issues)
3) I listen to calm inspiring music.
4) I already mentioned that therapy is beneficial.
5) I have to be proactive in my treatment plan. I have to take meds and if they don't work, I have to call my pdoc and be stubborn

and tell them I need a better med.
I really hope that you keep sharing here as many others will be able to help you with what has helped them.
Again welcome and I hope to see you around the forums. If you have any questions about this site feel free to contact any community liaison or moderator. Best wishes my dear.