I believe that babies can go through this at any age. Nina started to go through this at 5 months, but it didn't last long, only a couple of weeks.
The only thing I can suggest is for you to have people around you and bub as often as possible, and have them playing with her, heaps. And slowly, you can decrease the amount of time you play with her while visitors are there. Maybe just keep doing this until she's happy to be in other people's company.
I don't know, hopefully it'll work.
Good luck