The relationships of Tony Stark/Iron Man.
Rhodey is Tony's best friend and an officer of the US military. He often argues with Tony. He even stated that Iron Man can't do this alone, but Tony never listens. After Rhodes became paralyzed, Tony was shown helping him walk.
Pepper is Tony's personal assistant of Stark International and the Avengers Mansion. She always worries about Tony fighting alone against villains who stole his tech. Tony and Pepper eventually entered a romantic relationship. However, they have since "taken a break" after Stark's continuous Avenger work. After some months apart, the two got together, married, and had a daughter together, Morgan.
J.A.R.V.I.S. (Just A Really Very Intelligent System) is Tony's AI butler and caretaker of the Avengers Mansion and Stark International. Jarvis sometimes argues with Tony over when he will build another armor. He always assists him when Tony is fighting villains. J.A.R.V.I.S. would later be inputted into Vision, in an attempt to stop Ultron. J.A.R.V.I.S. is then replaced by F.R.I.D.A.Y..
Steve is Tony's ally, teammate, and friend in the Avengers. As for their social relationship, they might as well be considered as "frenemies" due to their personality clashes. Despite their differences, they truly care for and respect each other. When Scarlet Witch shows Tony a vision of the Avengers lying in the ground, injured and dying, Tony is especially affected by Steve's apparent death, as he quickly rushes to the latter's side, checking for a pulse. Their friendship is put to the test and severely damaged after the events of Captain America: Civil War. However, Steve sent a letter of apology for everything that had happened, telling Tony that if he ever needed his help, he'd be there. Tony, in turn, allowed Steve and the other Avengers to escape from the Raft, possibly showing sighs of forgiveness on Tony's part.
Bruce and Tony are good friends, getting along as soon as they meet, and share an interest in technology. Tony even encouraged Bruce to see the Hulk as a blessing, rather than a curse. After the Battle of New York, Bruce (as the Hulk) is the one to catch Tony when he's falling to the ground from space. Bruce would later assist Tony in creating Vision.
Fury is Tony's former boss (of the Avengers) and the two have shown an interesting alliance and Tony agrees (or sometimes disagrees) with Nick's decisions for S.H.I.E.L.D. and the Avengers. However, Tony has supplied with him along with S.H.I.E.L.D. some weapons from his suit. After Tony creates Ultron, Fury tells Tony that he cares about him. Nick Fury proved how much he cared for Tony by attending the fallen Avenger's funeral.
After recruiting Peter for his team during the Avengers Civil War, Tony starts mentoring Peter in hopes of helping him become a better hero that he himself had been. When Peter had been taking dangerous missions, Tony took away his suit, believing that it was for his own good. Once Parker showed responsibility, Stark gave him back the suit, as well as a place in the Avengers, but Peter declined. Once the events of Infinity War happened, Tony made Parker into an Avenger. When Peter was decimated, Iron Man felt that is was his own fault as he could've prevented his death. It was Parker's death that motivated Tony into helping the Avengers undo Thanos' actions. When the plan worked, Tony and Parker had a happy reunion. It did not last however, as Tony would sacrifice his own life to stop Thanos. Parker would attend his Mentor's funeral.