first of all, I feel pretty amazed that u feel uncomfortable with using respecting words. it sounds like u really have deep sense of those respecting words in Korea, and difference between common way to talk to friends and the way to talk to elders. Is the korean culture something you have to be born into in order to understand? yeah u're right. no matter u re close to anybody. u must add respecting words to them if they are older than you. it's Korean culture. Of course, There are some exemption. In some cases, older person who think they are very close to the younger one suggest to the younger one that u don't need to use respecting words. but it's hardly happening in Korean. only brothers and sisters in blood are supposed not to use respecting words. actually in my case, i was told from some elders that I don't need to use 존댓말 to them, but i just refused to their idea, 'cause, it is awkward for me not to use 존댓말 to them. it feels like I'm being rude, not polite if i don't treat them with 존댓말 even if they are close enough to suggest me not using 존댓말. don't feel uncomfortable to use '존댓말' it's just the door through which you can talk with elders in Korea. u can just say as 반말 if she allowed you to. but it's up to her decision. and I don't recommend you to bring up this issue with elders before they do.

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I've been studying Korean for 7 years and living in Korea for 5. The biggest problem with westerns learning languages that use honorifics like 존댓말 is that we're told that it means politeness and formality, which is only part of the story. You have to remember how important age is in Korean culture and language: If you and I are of similar age (0 to 2 year difference), but we're not close, we would use 존댓말. If we're of similar age and close, we can use 반말, but only after confirming that it's okay. If one of us is older, the younger one must use 존댓말, unless given permission not to use 존댓말 by the older one. The older one will use 존댓말 for a bit, but will likely stop using it once the two become more comfortable with each other. In the above cases, 존댓말 is related to formality and politeness, but in other cases it's just a grammatical system to convey respect. I know friends who use 존댓말 with their parents, colleagues who have worked together for 20 years and use 존댓말. My adviser at graduate school (20 years my senior) used 존댓말 with me because he respected a foreigner who could speak Korean (he eventually stopped, but my classmates said he used it longer with me than anyone else). Good use of 존댓말 is also a means by which Koreans evaluate your education level. If you're good at 존댓말, you sound smarter. 존댓말 is also safer than 반말, because it's harder to offend someone if every sentence you use ends with "I respect you." Don't take it personally. Your friend is probably just trying to protect you from misusing 반말. To be honest, after having lived here for so long, I prefer 존댓말 cause I'm exposed to it more often than 반말.

I've used 반말 with my friend for most of the time we have known each other, and she is one year older than me. If you really are close, it shouldn't matter that much, right?