Bruce
Tony Stark. Just like Bruce, he loved how intelligent you were. He also saw how beautiful you were and thought your shyness was cute.
Bucky
Sam Wilson. You were a strong, independent woman and he admired that. You'd also been in wars as well and would be able to understand him. He really did love how protective you were of the people you loved as well.
Clint
Pietro Maximoff. Ever since you met Pietro, you both hit it off. It was only natural for him to develop feelings for you. You were everything he wanted in a woman and more.
Natasha
Wanda Maximoff. She thought you were fascinating. Her powers didn't work on you and that just intrigued her. She didn't understand how someone as kind as you ended up with Natasha either. To her, you deserved someone much better...like her.
Pietro
Thor Odinson. You were so strong and independent. He loved that about you. It was often that he was found by your side and just listening to you or watching you. If he was being completely honest, he was sure he loved you.
Steve
Bucky Barnes. No one had been nice to him in so long that he was surprised when you greeted him with such kindness. You became like a rock for him. Whenever he needed comfort, you were there to help him. He really couldn't thank you enough for all that you did.
Thor
Steve Rogers. The thing that had Steve falling for you was just how cute and adorable you were. He thought blushing was awkward and weird before he met you. He couldn't help but be taken with your smile and your (e/c) eyes. It was common for him to catch himself staring at you longingly.
Tony
Bruce Banner. You were a literal angel in every sense of the word to Bruce. You were kind, beautiful, intelligent and, not to mention, the wings. No matter what funk he was in, just the thought of you was enough to chear him up. After getting to know you closely, he was starting to rue his shyness. He should have gotten to you before Tony could get his hooks in you and that was his biggest regret.