Sounds very much like Michel Jonasz, "Triste et bleu," sung Hapa Haole style (mixed English and French). He is a well-known songwriter and singer in Europe. Here are the first two verses; you can compare with what you know of the song:

TRISTE ET BLEU

Je t'écris d'Amérique, oh, baby. Yesterday night.
J'ai été écouter chanter Bo Diddley.
Quand il a demandé ou public "Are you all right?
Est-ce que vous allez bien?," j'ai répondu "yeah."

J'aurais dû lui dire en fait: "I'm feeling bad,
I'm down and out. Personnellement, je m'sens mal."
Je suis triste et bleu, sad and blue, sick, malade.
Je suis triste et bleu."

He goes on to sing about Margaritas served by Marilyn, Chicago blues, B. B. King, a Lincoln Continental. A great song. The part "in the shadow" I am uncertain about.
The entire song is available at Triste
One Hell of a lot of French songs of all kinds at this site, well-organized. Song titles