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Ianto Jones did not consider himself gay. In fact, he'd been attracted to what many in the twenty first century referred to as the fairer sex his entire life. At least, he was until he met Jack. Ianto Jones did no like men. Jack was an extraordinary exception. Jack was it, the light in his darkness so many times over that Ianto has lost count.
Ianto knows Jack can't love him back, not in the same way or same depth of feeling. He knows when Jack deflects personal questions with innuendoes and humor that he's throwing up yet another wall. He know when the lust in those kisses feels contrived, it's to keep up appearances, and though Jack loves sex, sometimes, he uses it as another shield. He knows Jack can't love him back because he sees Jack interact with Gwen.
Perfect Gwen, who can do no real wrong, who could break rules and regulations and could speak to them as though she had some moral superiority was held on some sort of pedestal. Gwen, whose eyes held Jack's with palatable tension, took everything away from him.
Ianto knows Jack can't love him. He knows he's just a poor, available substitute. Despite what he knows, he can't stop himself. Jack's kisses and roaming hands drug his brain into half-witted desire at the best of times.
The Welshman, buried deep in cataloging the archives, slid down the side of one of the tall shelved, cradled his head in his hands, and cried. He cried because he blamed Jack for his weakness, blamed himself more. He cried because if he didn't, he wouldn't be able to function around his coworkers.
He felt so… pathetic. Inadequate.
Ianto stayed that way for a short time, long enough to regain some semblance of control, but not so long that he'd be unable to hide the evidence of his emotional outburst should someone call on him unexpectedly.
After all, Ianto's good at keeping secrets. What's one more?