I am getting married in five weeks. We just mailed out the last of our invitations and my parents are criticizing our guest list. We excluded all guests whom we did not know and dates of our guests whom were not engaged, living together, married or who have been dating for a short period of time ( less than a year). My parents think that all of our siblings and our cousins should have been able to bring a guest regardless of whether or not they were close to us. I've read countless blogs regarding this matter and most have said you invite those that you are close to. How do I make my parents understand the difference between a casual relationship and a significant one and why you would invite one over the other? This is a topic that has come up countless times and seems to never be resolved. My sister has a boyfriend whom just moved away who she has been seeing less than a year. We had to cut our guest list in half due to our financial situation and he was excluded. Should he have been invited or should immediate family be allowed to bring a guest?
There really is no "time limit" that dictates a significant relationship. But, your views are mainstream on whether or not to allow dates.
All of this is written in etiquette books and on this site, which follows mainstream etiquette--not a chat room or blog. So, perhaps you could request that your parents read a book or come visit us.
If your sister and her boyfriend are very close, then it perhaps he should be invited. But, that is a very fine line. It really is your choice.