Not that I've seen, Shadow usually keeps more to himself, often blanking the world out in the process. So, I'd think not. Maybe off the scenes, yes, but not on film.
Besides, Rouge usually flirts with Knuckles, Sonic, and Tails, to make THEM blush. Ecspiecally Knuckles.
Don't forget that she kissed Tails in Sonic X.
Chat with our AI personalities
There are no canon couples within the Sonic series so far, whilst this may change in the future, it is highly unlikely that Rouge will tell Shadow that she loves him.
Everything has its end, even though Shadow the Hedgehog said to be immortal, if he were to live until the world ended, he would die along with the world.
That is unknown, and if they did, it would be in a friend type of way.
Maria is simply a made up hedgehog and if you have ever herd of sonic the hedgehog maria is one of our hedgehog heros.
He cried in SA2 when Amy reminded him of Maria's wish. And in Sonic X's adaptation he cried in episode 38, Maria's Request, Everyone's Request.