Lyric discussion by Bob Stein 

Cover art for Songbird lyrics by Fleetwood Mac

I agree with Josie713sg, this is a goodbye, letting-go song. The final line "I wish you all the love in the world, but most of all I wish it from myself" implying he will not be getting love only from her.

It's a very sad, a very loving, and the most generous goodbye song I know of.

My Interpretation

@Bob Stein agreed …..