AITK? My girlfriend wants to breakup with me because of the way I talk and act around my friends.

AITAH? My girlfriend wants to breakup with me because of the way I talk and act around my friends.

Idk but this seems so random. I don't know how to describe this but I'll try my best.

Basically I (26M) am Indian-American. Moved here for college and have been here ever since. My girlfriend is a third gen immigrant from India, her grandparents moved here. Both of us speak Hindi fluently but we only talk English with each other. Idk why but it just happened. Since we have been dating for a couple of years we decided to take a trip back home because she had not visited in about 5 years now and I had my yearly trip with my friends. We all decided that this time we should bring our girlfriends because honestly why not.

Here's where the conflict began. Since we were all raised back home, we all talk in Hindi. The thing is, we swear a lot, like a lot. All of our friends in the US are locals, with me being the only "foreigner" i.e. not born here one. I don't swear at all in English because I never got the habit and always found it a bit weird to swear in English. When we all met up, we started talking and by extension started swearing a lot. The way I talk in my language is also much different than how I speak English, because I developed an accent after living in the US for 8 years and I don't have any accent in my local languages. My girlfriend on the other hand, speaks both languages with an accent. The problem is, throughout the night, my girlfriend became uncomfortable, I asked her for a couple of times and I asked her if she's fine and she told me yeah, she then started talking to one of my friend's girlfriend. I know this makes me a bad boyfriend but I was so engaged in catching up with people I hadn't seen for a year that I didn't ask her again about that. The next morning, the guys left early cause one of us had rented a turf to play cricket for a while. My girlfriend woke up late and immediately called me and asked me where I was, I told her that one of my friends booked a turf for us to play on and I got a call in the morning, I didn't want to wake her up and told her that I'll be back in a few hours. She got mad and told me to come back now and that she's all alone at the Hotel and that she want's me to come back. I told my friend's I have to head back and came back to the hotel. At the hotel, she told me that she felt a bit awkward yesterday since nobody was speaking English to her. I told her that she speaks the language so I didn't really see what the problem was. She told me that she's not very confident in her skills and that she's much more comfortable in English. I told her that I have heard her speak and she sounds great and that she shouldn't worry a lot. This night, when we met, I didn't know how to bring up the subject and just told my friends that let's stick to English when we are talking to my gf and that its a "great way for you assholes to improve your English". I didn't mean it any rude way and everyone laughed at the joke and everyone had no problem with that. (language warriors please don't come after me).

Basically for the next few days the trip went fine and I had the time of my life. My girlfriend seemed a bit reserved and I just thought that she was having a culture shock because she hadn't been here in a while and all that. After the trip was done, we flew back to the states and on the first day back she told me that she was mad at me for the way I acted during the trip. I said "huh" and she tells me that I don't act the same way with here with our friends than I do with my friends back home. I told that's understandable because I have only known these people for a couple of years at this point and I know my friends back home for almost 15 years now. She then tells me that the type of language I use when I speak Hindi it makes me sound like an asshole. My reaction again was like what?. She then tells me that she's not okay with the way me and friends talk to each other, saying that it makes all of us sounds like assholes. I told her that's just the way we have been talking since we grew up and we are all fine with it. She also told me how open I was to spontaneous plans like the time me and my friends decided to go on a hike, after one of us drunkenly said that "we should climb X hill" or the time that one of us wanted to try skydiving so we went the same afternoon. I told her that we come up with spontaneous plans all the time and that I told her that spontaneous things can happen on this trip and she can say no if she wants. She didn't come with us for skydiving and hiking because she was "not prepared" for these and I had told her she can just come in her regular clothes and that were not taking any hiking gear with us anyway. (The place is so easy to climb, you can do it in Jeans). She still said no, so we decided to go on our own. She then told me I am more reserved with our friends here than with these guys and I don't make any stupid decisions. I told her that I consider both groups as friends it's just I have known these guys for longer. She told me that she wasn't comfortable with me making decisions on the fly and that we should have planned everything on the trip. I told her that I had already told her that spontaneous things can happen and that she can say no if she wants. I didn't force her to do anything. She told me that she thinks it's weird how I become a different person around these guys. I told her that she's overreacting and that it's fine, I also apologised if she was uncomfortable and that it won't happen next time.

She said that she is reconsidering our relationship now and doesn't know what to do next. We haven't spoken since yesterday. I have no clue how to react to this, I agree that I may act differently around people here vs home because I have not known these guy for my whole life. We had taken a trip upstate once and it was a very relaxing but it took months of planning and schedule clearing. Our trip happens every year at the same time and we rotate the destinations since some of us live abroad. I talked to one of my friends and he told me that his girlfriend also thought my girlfriend was acting very strange throughout the trip. I really don't know how to react to this. AITA?