But don't they all love him?

they do, but time passes, and people may go.

Ahh..I know that fear...honestly.
Fear of having to stand alone...but, there's an old saying
Fear has two meanings : Forget Everything and Run.

Or..the one some don't remember "Face Everything And Rise"
Basil's not alone. He's got friends and he is loved.
His fear...is just his own dark thoughts trying to betray him.

At least that's my take on it. I respect and would help this Delphox if he ever asked for it.

good apreciation of what he is thinking about =D

He tries his best to be a happy go lucky person, but sometimes, life can prove that to be difficult!

I apologize if it feels I'm waxing poetic. It's just Basil's not alone.
And if he ever feels he is. That's what friends are for. Like a safety net that catches ya