Very true, if you can help it it's nice to avoid it. Try making a plan in your head or here or in a journal of some kind, etc., about how to cope with your anxiety/triggers, maybe?
For example, what is your plan for that day? Are you going to go out to the zoo, the park, walk around the neighborhood? Stay home for self care or go to a friend's if you have someone you can visit?
What are your red flags for when you actually do need a hospital, and where would you take yourself to if you got to chose which hospital? (Just some way of control to make it less frightening, potentially.)
What will you do IF, not when, it gets bad? Will you come here to vent (with a timer so you don't accidentally ruminate and make yourself feel worse)?
You're starting off with a cognitive distortion, fortune telling -- predicting that you WILL be having a really hard time and might end up in a hospital. Maybe you did last time, for instance, but that doesn't mean you absolutely will this time. Maybe it'll be a bad day, but maybe you can do this THIS time.
It's okay to be nervous and afraid, so let yourself feel that in a safe place, and then make a plan for what you will do, when you know you're ready to cope and when you know you want to drive yourself to a hospital.
If you're on any medications, set a reminder to make sure you take them near the date.
What symptoms make you need a hospital, versus "regular" support?
Hang in there, and maybe plan something for the day after if you can <3