Is it ok to be 'annoyed' by just one bad habit?

After a long time of being together 24/7, my girlfriend is now away from me for the next 5 months or so, while she finishes university.

The only form of communication we have is web-cam over Skype, and my girlfriend has a bad habit that is driving me up wall.

She is a very very busy person, with university, part time work in a restaurant, helping her mother out at the market, chores, and a load of other stuff, so I have to be a bit patient.

The problem is, mid-conversation, without warning of any kind, she will stand up and vanish. She may be going to the back of the room to turn the light off for a second, or she may end up messing around with papers and things in another room for 15 to 20 minutes.

I have asked her a few times, to just say “brb”, as I do, out of manners, and if she is going to go do something for 15 minutes, to at least say something that hints at that.

If I could get her to just say “brb” or “gotta do some stuff, give me 15 mins”, then I would not mind at all.

I know she can’t help it, some people would not be able to cope with everything she has in her head at any given time, but it is just driving me insane.

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