I.Steve developed a hard core crush on her the day that she knocked Hodges on his ass, knowing that she didn’t like bullies either, that she would toe the line or blatantly cross it was the beginnings of his falling in love with her.
II.When he was running with the Howling Commandos, he always asked for her input first, Steve isn’t all that great on sneaking in, he’s a kick the door, start whaling on someone kind of person. So he asked her opinion on how to get there stealthily, and then kicked the door down.
III.After getting Peggy settled post that really awkward as hel reunion, Steve tried again to get drunk, and failed. When it did he almost tore the whole section where her body had been stored in cryo apart bare handed, trying to deal with his confusion, hope, and anger that she’d been subjected to that.
IV.He watches her sleep, not because he’s worried about her health, but because he’s still not entirely assured that she’s there, that she’s not a figment of his imaginations, or maybe he’s dreaming at the time and when he closes his eyes he’ll wake up without her. Doesn’t touch her or anything because he doesn’t want to discuss it, but he just watches her breathe and tries to find peace with it.