Struggling

Struggling on day 75.
I've always tended to be too much of a people pleaser. I tend to agree to do things I don't want to do, like go to parties or events or shows, go on vacations with people I don't know that well, or sign up for a fantasy football league (like today).
I never thought of myself as an introvert. I like to shop and go to bookstores and have one-on-one meals with people. But I don't like parties or events or vacations with groups of people very much at all. I get really tired. (In fact, I'm typing this from a party right now).
I used to gamble to take the edge off. It made my life easier. But here we are. I'm stuck at this party for at least another hour or two. 
I need to learn how to take a deep breath and just stop. Just stop saying yes. Stop doing things I don't want to do. Stop going to parties whenever I don't want to go. Stop signing up for things I don't want to do. Just stop.
I could be reading right now. I could be seeing a movie. I could be dancing or exercising or making smoothies or sleeping or resting or walking my dogs. 
This just is not my cup of tea. No matter how I try, it's not. I can't pretend to be someone I am not. Not without the gambling or alcohol to get me through, and I don't want to do that.