what about those people who choose not to recognize it as a marriage......just as some do not recognize killing an unborn child as an acceptable form of birth control......
You can choose to not recognize it as marriage, that's your personal choice. If you are required by law to treat a married couple a certain way, you will be required to treat all marriages that way, but you can still personally not consider it marriage.
If you don't want to invite them over for dinner, you will not be forced to do so.