We are supposed to go on vacation with my ex and I'm dreading it.
What makes you nervous about it? Do you and your ex not get along?
I just think it's going to be awkward and weird.
Well, I mean that is your ex after all. Most people wouldn't want to spend their vacation with their ex, so I understand.
I know it's not right the way I'm acting. I have to conquer the anxiety.
There's nothing wrong with not wanting to spend time with an ex, especially a vacation. If you don't feel comfortable with it, just tell your ex ahead of time that you won't be spending time with them. If your ex has to be there, just interact with other people instead!