A six-month crash course in Korean is a lot more than the average traveller would invest in a trip
The Korean alphabet is actually quite easy to learn. Vocabulary is more of a challenge.
If your friend looks the part, it would be wise to advertise her western background at the beginning of a conversation. Visiting/returning Korean-Americans usually elicit a measure of sympathy, especially if they try to speak Korean.
The key is not to be mistaken for an ethnic Korean illegal alien from China (there are large numbers of them doing menial jobs), or god forbid, a North Korean spy! This only applies to ethnic Chinese and Koreans, as locals can easily identify other Asians.