Why I Don't Get Excited for Wedding Season

Since wedding season has wrapped up, I thought now would be a good time to write this. This is probably going to be one of the most brutally honest and vulnerable posts I have ever written. Based on the title, you probably think this is going to be some rant about being single and seeing wedding pictures on Facebook, but it's not. I do have a wonderful boyfriend, so this isn't about that.
When I went away to college, I met some of the nicest, coolest, sweetest, most fun people I have ever met in my life. For the first time, it felt like I had a real "squad," people who actually enjoyed having me around, and didn't just tolerate me. I had a solid circle of friends.
Throughout my time in college, a lot of people told me to prepare to receive lots of wedding invitations in the years to come. A lot of people get married not long after graduation. I was so ready for it. These people meant a lot to me, I was super happy for them, and I wanted to celebrate with them.
Graduation day was a year and a half ago. Some friends got married before then, and a lot have gotten married since. There have been roughly 25 weddings, and that's only those involving my college friends, some of which where I had been friends with both the bride and the groom. How many of these weddings have I been invited to? One. That's right, 25 weddings and I was only invited to one.
The one wedding I was invited to was that of my roommate from freshman year. Sadly, I was unable to attend due to it being far away, not having a car, and having finals. She said she figured that would happen, but she still invited me. I still have that invitation somewhere among my college stuff.
One friend's wedding happened while we were still in school. When she first got engaged, she had told me I would definitely be invited to her wedding. My best friend and I were both invited to her bachelorette party and her baby shower, but neither of us were invited to her wedding.
Many times when I talk about this subject with friends they say, "Well maybe it was a small venue and they could only invite so many people?" Look, I understand that kind of thing. The problem is, many times when photos from these weddings surface online, everyone else we knew in college is there. It's hard not to feel left out. And it's kind of hard to believe that out of 25 weddings, only one had enough space for me.