Was I wrong to feel hurt after being left out of my friend's wedding party?

I want to preface this by saying I don't want to make this about me, nor am I acting entitled. I was genuinely hurt.

My friend Sarah (fake name) got married today, we known each other for since elementary school but didn't start hanging till middle school. Her and I were never close per say but she would invite me to functions like friendsmas and friendsgiving, and out drinking. We never spent one on one time together. She's been that "friend", but when we hung it was always in a group cause when I hung with her one on one it was awkward cause we never did it.

When we all graduated we all kind of split apart, didn't hang much in the friend group. Friends went to college, I kind of isolated myself from the friend group. I work in healthcare so weekends were never time to hang, and I am gonna admit. I was flakey, and cancelled a lot. Which now I regret.

But, going to the wedding today ALL of my friends were in it besides me. I sat alone and had nobody to talk to or chat with till after the wedding. I only went to the ceremony, and I decided to leave.

I thought her and I were closer than we were I guess, but seeing that really hurt my feelings. And now I feel like I wanna cut all of them off, cause how I felt was lonely and hurt.

Am I in the wrong? Am I overthinking this?

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All of my other friends in that friend group were in the wedding, including the guy she was friends with at one time.
Was I wrong to feel hurt after being left out of my friend's wedding party?
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