I can't be a normal partner because of Hashimoto

I’m really struggling with constant fatigue and this overwhelming need to just rest and digest everytime after eating.
It happens whenever I go out with my boyfriend - we can't even have a nice date and dinner, cuz I am immediately tired. (This isn’t about him - I’ve been like this for as long as I can remember).
Today, for example, we went to a big family birthday celebration. And guess what? I ate some food… and I completely crashed. Once again, I’m no fun to be around. All I want to do is lie down and rest. For my body, simply digesting food is fucking exhausting. And that’s not even mentioning the fact that I’ve been falling asleep everywhere since I was a kid.

Damn.

How am I ever supposed to have my own wedding if I can’t even stay awake or feel well after eating? I either get incredibly sleepy or I just feel awful.
I know my stupid thyroid is a big part of this.
How can I improve this? I just want to be a normal, functional partner - not the boring one who slows everyone down or ends up ruining every outing.

My antibodies are 180
My TSH is around 7