I don't know why invitations stress me out. Let's analyse.
One, because I'm a people pleaser and I feel bad turning others down.
Second, because I feel sorry if I don't fulfill their invites.
Come to think of it... why would I disappoint them? I may... but I am not that important to begin with. Also, I think people recover quickly. And they'll most likely find replacements in no time.
And I have to prioritise myself too! Sometimes I feel obliged accepting invites to the expense of my own happiness - I mean, I need time for myself and do whatever I've long planned to do. Or I simply feel the event does not benefit me in any way.
Yup, I guess now I know why. Thanks for analysing this with me.