It's along fic, and Tony gets really sick (I think it's terminal, and i think he dies at the end)
It's a Steve/Tony fic, but i think that he's with Pepper at the start, because she ends up pregnant with his child, but they break up before she knows about it.
Pepper doesnt know that he's dying, and I think she's together with Happy later.
Tony just gets sicker and sicker as it goes on, and at one point he and Steve go to the beach late at night, and are coming back on the Subway, and Tony is sleeping on Steve's shoulder, and this lady on the train asks if he is sick, and Steve says yes, and she says that her husband looked the same before he died.
Also, I think at the start he is drinking alot and maybe taking alot of pills to mask the pain, and they kindof think that he's just being self destructive.
And he eventually goes for one last flight in the suit even though they say its too dangerous, and he almost dies doing that... i think.