I have friends, but they make me feel lonely. What's wrong?

I have friends. We hang out regularly, both one-on-one and in groups. They've invited me to parties, and I've invited them.<br><br>But they don't seem to enjoy spending time with me. They seem to tolerate me. They enjoy spending time with each other, but not me. And I just don't understand it.<br><br>Sometimes I make a joke and they politely laugh. Sometimes they just stare at me as if to remind me that, yes, I did just say something. I feel like I've made an inappropriate comment at a formal event.<br><br>I have one friend who is amazing, and we have a great time. But the rest just feel... tolerated. Is it me? Am I so boring or obnoxious that they just put up with me because we've been friends for a while?<br><br>I've tried being a better friend. I've tried standing up for them. I've tried listening and empathizing more. I've tried being more outgoing and making more comments. It doesn't matter. It's like I'm invisible to them.<br><br>I'm tired of feeling lonely. How do I make them enjoy spending time with me?