No, it doesn't. It can happen if you go to another country speaking the same language with a different accent, to some degree.
It can happen if you go to a foreign country but they all speak english and their accent affects you, to some degree.
It's virtually impossible for a native english speaker that grew up in this country, that spends some amount of time overseas (but still spends most of her time in the US from what I can tell) to have a complete degradation of her native tongue to the extent we see here without some degree of intent.
I just can't see it. I've lived overseas for long periods of time. I've had many, many friends in exactly her situation (but not the same country or language) and never have I seen anything like it. Some words may change, some strange usages crop up, but the base is still there.
This sounds like english is her second language.