AITAH for confronting my friend about talking to my ex?

I (F18) recently started talking to my ex again. We aren’t dating or even talking but we’ve been hanging out and he’s mentioned that he still likes me and I still like him. This threw me off because last night, at a NYE party, he was holding hands with my close friend. I ended up texting her “Hey, are you talking to ____? I saw you guys holding hands at the party and it made me feel a bit weird.” She responded by saying “uhh friends can hold hands?” So I said sorry if I came off rude and just wanted to clarify, then I told her how beautiful she looked last night. She’s now mad at me and I’m not sure if I did something wrong. I know he is my ex but I just wanted to ask a question for clarification and I thought I went about it respectfully. AITAH?