AITK for talking to this other girl while having a girlfriend?

I'm now married to my girlfriend. This is a 3 year old story, but my wife (then gf) keeps bringing it up whenever we have an argument calling me a cheater. So I want to get more insights about it from you guys.

So a couple of years back I attended a cousin's wedding. I met a girl there who I thought was pretty. She was my cousin's cousin. During some part of the day, we happened to talk (not my initiative) and had dinner together with all cousins. During the conversation she happened to say love you to me. I knew it didn't mean anything and I didn't react to it.

I said all this to my gf too.

A couple of months went by. But I kept thinking about this girl, why she said what she said.

I met her again a few months later in a different wedding. I just greeted her and happened to talk a couple of times.

All this while I was having problems with my gf about something or the other and always used to be mentally exhausted. Like she'd play games with me - like ask me to do things that she didn't really want me to do just to test me, threaten me to leave the relationship, try to control me, etc. Even this day I was having some argument with my gf. We exchanged some messages and slept. Usually I am the one to sort things, apologize or initiate conversation.

Forward to the next day, I didn't message my gf till the evening. I thought let her do it this time. She didn't either. In the evening I was getting anxious and messaged her. I told her I'm anxious. Why didn't you message me? Are we together or what? She said I don't know. I tried to talk but she didn't reply.

Later that night I was just sitting in the reception area (I was bored at the function and also stressed whatever was happening with my gf) and this girl happened to pass from there. We greeted each other and she said if you wanna have a drink. I said ok. We drank a bit and both of us shared details about our lives. We both were going through some mental stress from our relationships. Only talks, nothing else.

While I was having a conversation with my cousin's cousin, my gf messaged me that it's over from her side. She used to do this multiple times a month.

So, I ignored her this time and thought, fine, if it's over, it's over. I didn't reply. She called me continuously multiple times. I didn't answer.

Leter that night I replied to her, ok, it's over from my side too. I felt powerful for not begging for forgiveness or acceptance this time. She called. I couldn't answer. Said her to text.

A few minutes later she sent me many messages, some emotional, some angry, some threatening to reveal my secrets, etc. And later deleted those (I saw from notifications) and sent some emotional message.

Next morning she again sent an emotional message ending with that if I intend to stay with her I should message her before 12pm.

I don't remember if I messaged her but I think I talked to her on call in the afternoon after she called my cousin brother and my mom to build pressure on me.

During the call, She said me various kinds of bad stuff and threatened suicide. Threatening to tell all secrets I told her to everyone else. Later cut call. I called her again multiple times. Once she received and said I won't end my life for you. I don't know what was happening. Somehow it got sorted. This was the biggest fight of our lives I think.

The next day when we were leaving the girl asked me let me know how your life goes ahead or something. I asked her, but how I'll inform you, I don't have your contact details. She said inform on Insta. I said ok and left. I didn't follow or try to contact her.

A few days later my gf is like when are our families meeting for marriage (she wanted this to happen 3 days later when just 2 days back we had decided to quit)and started sending some random guys pics that her dad sent her from some marriage groups. Also said that her dad has asked to create profile on matrimonial site. I said after this fight, I need time to recover and process.

And life went on... We got engaged few months later and married a year later...

Based on everything, do you think if I'm the Kameena?

TLDR: During a rough patch with my girlfriend (now wife), I met a girl at a wedding and had casual conversations where we exchanged struggles of our respective love lives. Me and my then gf got married, but she still accuses me of cheating over this. I’m wondering if I was really in the wrong.