Okay, I feel I should explain myself. This hasn't happened per se, because it's not my actual reaction to getting a wedding invite. The momentary jealousy and feeling of "Oh crap, I'm going to die alone" is quickly overtaken by feelings of joy for my friends who're choosing to tie the knot. I just really thought this would make a funny comic.
I do feel it's necessary to apologize to all my married/engaged friends, though. I'm very sorry. I do want to come to your weddings! (please don't un-invite me!)