D'Artagnan followed them.
He had not gone twenty steps before he became convinced that the woman was really Mme.Bonacieux and that the man was Aramis.
He felt at that instant all the suspicions of jealousy agitating his heart.

He felt himself doubly betrayed, by his friend and by her whom he already loved like a mistress.

Mme.Bonacieux had declared to him, by all the gods, that she did not know Aramis; and a quarter of an hour after having made this assertion, he found her hanging on the arm of Aramis.
D'Artagnan did not reflect that he had only known the mercer's pretty wife for three hours; that she owed him nothing but a little gratitude for having delivered her from the men in black, who wished to carry her off, and that she had promised him nothing.

He considered himself an outraged, betrayed, and ridiculed lover.

Blood and anger mounted to his face; he was resolved to unravel the mystery.
The young man and young woman perceived they were watched, and redoubled their speed.