Am I insecure or were my concerns valid?

I'm sitting on my couch, missing her, wondering if she’s celebrating valentines with someone or not, thinking about texting her. But I can't ignore how badly our relationship ended. Even now, we both blame each other for the breakup. So, I wanted to ask you guys, where's the line between insecurity and being right? Here are some of the main issues I had with my ex: 1. She was still connected with her ex on Instagram. When I asked why, she said it didn’t affect her. I then asked if she’d remove him, and she refused. 2. A couple of guys at her office had already asked her out, one of them multiple times. I said just block them from insta and WhatsApp, but she didn’t. She said that they were teammates and she needed to communicate for work. 3. She frequently added random people on Instagram. Once, she added a guy who later left a flirtatious comment on her post. When I asked how she knew him, she said he had sent her a request, and she accepted it just like that. She had also added a few guys from Reddit. Now, I don’t want this to sound like our relationship was toxic or one-sided. I was certain she was the one, I wanted to marry her. We even lived together for two months, and that time was amazing. She loved me too, I’m sure of it. But when I moved back to my hometown, that’s when the issues started. She doesn’t have any female friends in Gurgaon, where she works, so on weekends, she’d go out with her male friends. I tried not to be petty about it, but she went out with different guys almost every weekend—about 3–4 times. One of them was a guy she met on her PG terrace (it was a co-living PG). They became friends , and later, she told me he had asked if she wanted to kiss. Even after that, she still went with him to Old Delhi to try different cuisines. It frustrates me how easily guys become her friends. And whenever I brought up these concerns, she’d get angry and block me. From her perspective, I was insecure, controlling, and even psychotic at times, especially during heated arguments. And yes, I admit I did act that way when we fought. But when I reflect on everything with a clear mind, I still feel she was in the wrong. She, on the other hand, believes she can’t be with someone as insecure and "small-minded" as me. Our relationship lasted a year, but even after breaking up, we kept arguing for another year. So, I genuinely want to ask, especially from a female perspective, was I wrong here? I tried to be okay with her having male friends, but over time, it became really hard. She always said she couldn’t get along with other girls and that boys made better friends. But in my opinion, when a random guy sends you an Instagram request, he usually doesn’t just want to be friends. She never agreed with that. What do you think?