Hypothyroidism Blues

So I finally went to a doctor about my exhaustion and he suspected hypothyroidism. I was convinced he was wrong because I’m thin and weight gain is a common symptom. I had my heart set on anemia. He was right, my thyroid is through the floor and now I’m having a lot of negative thoughts about needing to supplement with hormones as I tend to lean towards the “natural” side of life but I haven’t found a way around this one, and I know I’m fortunate because the doctor I see is supportive of natural treatment when appropriate. I tell myself I’m lucky to be born in this time when there is a treatment available because people used to die from thyroid failure. I’m fortunate I decided to take care of myself by seeing a doctor, but I’m not moving past feelings of grief over body parts malfunctioning and getting older, which are maybe some of the things I really need to work on because I’m resisting that reality and making it bad in my head, like I screwed up somehow and now I’m on my way out blah blah blah. I suppose that life is fifty fifty, but lately I’ve been on the happier side of fifty and I’m also scared the pendulum is swinging back and I’m imagining all kinds of other things going wrong. (Car accidents, crime instability where I live, one of my kids getting sick, etc, all the catastrophic things). I’m also wondering if it’s just ok to be sad about losing thyroid function and getting older. And maybe I’m desperately trying to find a different thought just to make that go away and not feel it. I’m not sure, I think I’m on to my brain a lot more than I used to be, but I’m confused about this one.