How to uninvite a coworker that quit

So I wanted to invite my boss to my wedding but I work for a very small firm and besides me and the boss, there is just one other employee. I wasn’t very close to this other employee: she is older with a family and kids in college and to be honest we didn’t get along that well. BUT I felt awkward inviting my boss and not her since that would’ve been very obvious she was being left out. 2 weeks after I finally gave them both an STD, this coworker quit. By the time the wedding comes around, it’ll have been 3 months that I haven’t seen or spoken to her since she is at a new job... in this very specific situation, can I just forego sending her an invite? Or do I have to suck it up and just hope she doesn’t come? We are tight on budget and already had to cut some other valuables to accommodate for guests like her, and if she comes with her husband that’s a big ticket for someone I don’t really want there. I know etiquette, but I’m just wondering what others think... help?