The Speech 

Invite your partner along, even if you don't actually know him/her. After all, you can't expect someone to do without their steadfast partner at your wedding. The emphasis here is on "permanent partner."  

Of course, the acquaintance from last weekend should stay at home, unless you want to get to know them on this occasion. 

In any case, find out about your current marital status because a normal wedding invitation card to "you" can bring back unpleasant memories for relatively newly widowed or divorced people. 

You can also officially invite people you do not want to have with you at the celebration or simply did not make it on the guest list to the wedding service and the possible subsequent champagne reception. That is always better than excluding these acquaintances entirely. Simply use two different texts: once with and once without the invitation to the party.