The way I see it, Jack's capable of two types of relationships: Fun flings, which are what he tells "amusing anecdotes" about, and loving relationships, which he doesn't talk about. Sadly, I think Ianto is just a fun fling. Which is sad, because Jack doesn't seem to have any respect for his flings. They're just jokes to tell to other people over beers. But the people who he loves and respects... he keeps in a box (or a jar ;)) It's especially sad because it's pretty clear how much Ianto loves and respects Jack. Maybe Jack does love Ianto in some way, but I haven't seen much respect on Jack's part.