AITA for visiting my boyfriend without telling his best man?

I (24F) met my boyfriend (27M) on a trip to Europe in 2019 and was only supposed to be there for five months, but I loved him so much I decided to stay. We have been living together for almost two years and he's the love of my life. I'm planning on returning to my home country in around a year or two, and I don't want to leave without visiting my boyfriend. However, I've been questioning our relationship because he's been acting strange. <br><br>He has two close friends from childhood, one is his best man and the other is a groomsman. About two months ago, my boyfriend told me that his best man's family had invited him on a trip and he thought it would be a great opportunity for us to spend time together without me around. I was hesitant at first, but agreed since I wanted to surprise someone else in my life at the same time.<br><br>I didn't tell his best man about my trip, but the other groomsman was aware. Before I left, I made sure my boyfriend had everything he needed, including a schedule and a list of emergency contacts. While I was away, I received a message from my boyfriend's best man saying he was shocked to hear I was out of town and asking if everything was okay. I explained that I had to visit someone and he understood.<br><br>The four of us have dinner together every month, and during our last dinner, my boyfriend brought up the trip again. He said it was great to have some time to himself and that he appreciated the opportunity to reset. I replied that I was also happy he had the chance to spend time with his friends and family. My boyfriend then asked if I had told his best man that I was out of town, and I said no, I hadn't. He got upset, saying he didn't understand why I wouldn't have told him.<br><br>AITA for not telling my boyfriend's best man about my trip and for visiting on my own? Or was I right in not sharing this information with him?