It was strange, the moment when Ianto realised how little Jack really cared for him. It wasn't because of Owen's constant remarks, or the way Jack looked at Gwen and flirted with other people, or even the way disappeared for three months. Those things he had so easily been able to rationalise away – Owen was wrong; Jack's flirting didn't mean anything, he was just friendly like that; Jack had to go and hadn't had time to leave a message and when he realised how long he was going to be gone for he did try to phone. No, it wasn't any of the things that would have made any normal person stop and think; it was something entirely different.
That morning, Ianto had woken up tangled in his sheets next to Jack and he had felt completely sick. Rising shakily, he had stumbled to the bathroom and emptied the contents of his stomach into his own toilet. After cleaning up and brushing his teeth, Ianto had taken his temperature to see it was much too high for him to go into work.
He had dizzily walked back into his bedroom and shaken Jack awake. On telling him that he was sick, Jack had replied with nothing, not one hint of concern. Frowning, Ianto had told Jack he wouldn't be able to go into work but that Jack should go back to the Hub. He had expected protests, the sort a normal lover would give. Instead Jack nodded, showered and left.
Feeling thoroughly miserable Ianto had retreated to the couch with his duvet and DVDs and waited for a phone call from Jack to check up on him. It never came. Gwen visited - she checked his temperature, cooed over him and even - Ianto had laughed at this - brought chicken soup.
Jack hadn't even visited Ianto that night. It was a peculiar way to come to the conclusion that there was just no changing Captain Jack Harkness. No amount of willingness, adoration or affection could break through and be reciprocated. After all, Jack had felt it all before. What would make Ianto any different than the rest of broken-hearted lovers Jack had left behind?
It was this stunning revelation that made Ianto realise that maybe it was time to move on. Jack had been right about Ianto that first morning: he always was a bit of a drifter. He had always got to the point where he knew there was more for him to see and do in a job and now, after four years working for Torchwood, Ianto had reached that point. Really, there was nothing left for him here. No family, no caring lover. This meant it was with no regret that Ianto Jones had phoned Martha Jones and asked her to make a telephone call for him. He didn't even hesitate when compiling a list of all potentials to fill his, Toshiko's and Owen's places at Torchwood Three. No, the only time his resolve even flickered was in writing a letter to Jack saying goodbye because, despite it all, Ianto did love him, irrevocably. It was just a shame that that didn't mean anything.
And now Ianto was off, travelling the stars in a blue box with a wacky Time Lord and a loud-mouthed woman. Making coffee and saving the world. Suzie was wrong, there's a job you can do after working for Torchwood, it just wasn't on Earth.