Some people always stay in "supporting roles".They are not made to play the lead no matter what. They are either nice and likable or just funny. And that's all they ever will be.
Just like comedians WILL get laughed AT and not just have people laugh WITH them.
It's not fair.
But that's life and it stays that way. The sooner we accept it, the better. Why is it still difficult? I guess because we all want the lead and strive for it and failure hurts. Second best is not the same. Best in support is good and satisfying but it leaves you striving for more. Some of which you will never get.