@NightFury i hear you sweet. Having mixed feelings is natural. You've been working on your mental health and you still continue to do so, so that's something that will continue to improve over time. I know it's hard when you don't feel ready to go back to work but need to financially, it's a really tough spot to be in especially with the way the cost of living is.
Being anxious around all of this is very normal. It's a big change and you're right in that there's alot of new things to learn and manage. Remember all those years ago when you started teaching, you didn't know what you were doing then or who you would be working with etc. But you learnt, you grew with the job, you made connections with people and you found your place. I believe the same thing will happen now, yes it might be hard to start with but one little step at a time and you'll find your way through it sweet.
As for not being ready, if you give this job a go and it's not working out then we sit and re-evaluate things. That's the beauty of life, nothing is definite or final, our futures can always be changed however many times we need to until we find exactly where we want to be in life.
Breathe sweetheart, things are scary (I'm not doubting that), change is hard (this i understand all to well) but you've got us here on your side working with you every step of the way, you've got some supports outside of here with more hopefully joining you soon to help you grow and recover. You've got this and we've got you always ❤️.