Is this normal or was my ex just abusive?

I’m a guy. My ex used to tell me that she didn’t have any guy friends, as she didn’t believe you could just be friends with a guy. Either you liked him or he liked you.

Because she was my first girlfriend I kind of just believed what she said and applied it to my own life. I didn’t have any friends that were girls. I actually got into a lot of conflict over this. When I told my guy friends, they thought I was super weird. When I told girls this, they thought I was very insecure. I just wanted to be loyal to my girlfriend. I burned a lot of bridges and prevented the formation of new ones for a very long time.

Fastforward 2 years and she cheated on me. For even longer after that, I had no girl friends, and very few guy friends. Looking back on it, I think she was a super insecure person. I haven’t been in a relationship since, as I’m still trying to get over it 6 months later.

Was this normal behaviour? Please let me know