How to tell guest their SO isn't invited?

It depends. Some people say it is rude not to invite a significant other. Well I do agree however, I also agree that it is your wedding and you invite whom you can. As long as they are not engaged or married, sorry but He is a boyfriend. Its your choice to invite him or not. If you invite only her and she decided not to come then she is also entitled to that.

If anyone invites me and not my spouse, I WOULD NOT attend. I never thougth any past boyufriend was that significant to take with me to a wedding although I accompanied them when they were invited to weddings. Its up to you.

Spouses are not "plus ones"

Plus ones are dates for truly single people.

Big yikes. A “no ring, no bring” policy is pretty outdated - and it ignores couples who may be serious but may not want to marry - ever. (Domestic partnerships can be legally valid, but not marriages). Some couples also don’t opt to wear or even buy rings, so the phrase itself sounds like it belongs to someone’s grandmother. If guests are over the age of 25, a plus one is mandatory, especially if you’ve invited other married couples who they know. Otherwise, you are effectively making them go alone to hang out with married people they know. Incredibly awkward. If you need to shorten your list, then you need to leave people off - but you shouldn’t be shaving down on the plus one size. Just because you’re holding a wedding does not make you entitled to being exclusionary or making people feel bad so you can add more people. Be thoughtful in how you include folks’ partners or families. If you can’t afford a big wedding, then don’t try to have one. Make it small and intimate and leave acquaintances off. If you break these rules, keep in mind, you will strain relationships and likely be discussed negatively.

View Quoted Comment I wouldn’t do this - you’re going to reap gossip.

The best way is honesty I think. Tell her you think exactly what you've told us. She will know what he's like, and if she understands she understands and if she doesn't she doesn't. But I honestly wouldn't let him come, and it's yet another reason why I'm worried to go to my best friends wedding, because I genuinely hate the majority of people there.

View Quoted Comment

Be careful doing this. My sister in law did basically the same thing; when her friend got to the reception hall and saw a few tables with empty seats she called her bf and had him show up.