Tony Stark has been called many things; Genius, Billionaire, Playboy, Merchant of Death, Philanthropist, Narcissistic, etc. But he doesn't believe he's any of the above. In fact, he knows he isn't.
Genius? Yeah sure, he was able to build a computer by the time he was four and graduated MIT when he was 17. But Tony Stark doesn't believe he's a genius. On some level he realizes that he is smarter than those around him but more or less he sees it as a curse. One of the many curses that have kept him from a believable existence.
Billionaire? Yeah okay, his dad single-handedly monopolized the weapons market. All the money he has is either from what he inherited or the money he has made from his father's company. He can't rightfully call himself a Billionaire when he wasn't the one to have worked for all of that money. Not initially anyways. The second curse in regards to him. He can rightfully say he only had four true friends in his entirely short life so far. His old family butler that had cared for him. His A.I. that he created in that butler's memory. Virginia Potts, whom he affectionately calls Pepper, who is his PA/CEO/Girlfriend. And Colonel James Rhodes whom he calls Rhodey. Everyone else was after his money or part of his fame. (Fame he didn't believe actually belonged to his own merits anyways.)
Playboy? He could see where this one came from. But honestly those women were trying to take as much advantage over him as he did with them. So he believed that it was a win/win for all involved.
Merchant of Death? Actually he couldn't deny that one. Ignorant or not he should have been more responsible with the state of the art weapons he manufactured. They never should have been in those terrorists' hands.
Philanthropist? Before he had his eyes opened Pepper was the one in charge of all those kinds of things. Then he openly made an effort to support charity work and help others. It wasn't compassion that drove him but guilt. He didn't do it to make other lives better. He did it to atone for all the horrible things he's done.
Narcissistic? Well he knows that's not true. It's a shield he's layered over himself for his own protection. One of the very many layers he's concocted to keep himself from getting hurt.
Because Tony Stark knows exactly what he is. He's an abused little boy who's had his trust trampled on too many times.
So when he offers his home to the other Avengers it's not because he trusts them. Oh no. It's because it will make things easier in the long run. He knows that he at leasts likes his teammates and so he makes them better equipment. But he wont trust them. Everyone always leaves him in the end.
But as time goes on and they are sent on more and more missions Tony finds himself creating and upgrading equipment for his teammates as much as he does for himself. He realizes that he is starting to care.
When he realizes this he starts pushing.
And then he notices that his teammates are starting to care for, maybe even trust, him as well and he knows he doesn't deserve it so he pushes even more.
It's not until Steve A.K.A. Captain America blows up at him and calls all of his bullshit and rips apart his carefully laid protections that he looks around. They're all standing there with that look of knowing and understanding. It makes him realize that they see past all those layers to who he is. Even though they know, they are still there and haven't left him.
And he gives them all a smile as he takes a step back. A real smile that those in attendance have only ever caught a glimpse of and he turns his attention back to Steve and gives him the only response he could. "Well damn, Rogers, you just figured this out?" He smirked as everyone laughed and he pats the captain on the shoulder as he moved past him to pick up the smoothie JARVIS had made for him.
Maybe, just maybe, he didn't have to keep pushing so much…..Nah it's too much fun.