Being a floater means never really fitting in anywhere or into a particular group of friends; sometimes an after-thought, sometimes a pity invite. You just bounce around different groups and cliques, knowing a few people in each group but not actually being in that group. It's not something you can or want to blame on anyone else, though, that's just the way life happens.
Floating is kind of hard to describe. It's not total rejection because people still accept you. A person will be friendly with you, even spend time with you and get close to you... but it's never enough to be initiated into their larger group of friends. This is pretty much the basis of most or all of your friendships. To be honest, you've never been able to call a set group of friends your own, and you've grown to be okay with this.
But then the drifting starts. Your friends strengthen their bonds within their own friend groups, and you start falling through the cracks. They're not purposely forgetting or excluding you, but it's also not their number-one priority to keep you in the loop since you're technically outside of it to begin with.
It's like a sort of vicious cycle – you make friends with someone that has other closer friends, you try to maintain a friendship, you lose it to the fact that you joined the group a little too late, and repeat. You know no one is to blame, but you start to wonder if there's something wrong with you... if maybe the blame should be placed on you.
You start feeling like you're not smart enough for your scholarly friends, not athletic enough for your friends on sports teams, not talented enough for your musically-inclined friends, or just not good enough in general. You try to make changes to your appearance, your attitude, your demeanor, your opinions, anything to make the next friendships last a little longer.
However, there's a strange bittersweetness about having to start friendships from scratch. That clean slate allows you that opportunity to be proud of who you are. If you look at it in a certain light, it teaches you to see your true worth and helps you to accept that, if the friendships you share with people start to fall apart, there are better ones out there to be shared with people that will appreciate you!
It is not your fault that you are a floater. Fitting in is not an easy feat. Don't blame yourself for feeling out of place or lost. Keep being yourself, never falter just because you think it will make others like you. You learn to love yourself enough to accept that you're a floater and that that isn't a bad thing – you're just so diverse and unique that you need to share that awesomeness with more than just one type of group. Look for people who will accept you no matter how weird you are. They're out there somewhere.