My ex called someone “daddy” a year ago.

We had been together for 1 year and 2 months and I broke things off last June for the sake of my mental health because long story short she played too much.

Today I heard from a guy that my ex girlfriend called him “daddy” in person around a year ago when she was tipsy and walking with her friends, and one of her friends even intervened and had to stop her. The guy himself doesn’t make me insecure at all, and he felt weird by the whole interaction, but I’m so upset by her principle. It has disrupted my healing journey of 5 months. I don’t know why I’m so bothered, please give me some support.

Note:- The guy only spoke to me because he for some reason still feels weird about the incident. My ex and him never spoke or anything before or after. They were only involved during that incident.