Tony Stark: He thinks that he is not smart enough for you. Since you have a master's degree in education and he only has a bachelor's degree.
Bruce Banner : The other guy is his insecurity. He is afraid that the other guy will come out one day and put your life in danger. He doesn't want to see your life in danger so if he hulks out he has you move to a different room.Steve Rogers: His insecurity is his beautiful blue eyes. He thinks that his eyes are ugly and boring. He says that everyone has blue eyes. You love his eyes and you tell him that everyday. He will look at you with love and adoration. You tell him that you happen to love his eyes and don't care what other people think of them.
Bucky Barnes : Now Bucky has two insecurities. He thinks that you don't know about his insecurities but you do . You knew that he is insecure about his arm and his teeth. He thinks that his arm is a no good for nothing weapon. You love his arm so to show him that you love his arm you will place soft little kisses on it . Now with his teeth you love that they aren't perfectly straight . You love how they are slightly crooked .
Sam Wilson: He was insecure about his smile. He never did like the way it looked in mirror . You tell him that he has such a wonderful smile.
Tchalla: He doesn't have any insecurities.
Clint Barton ; He believes that you deserve better than him . He thinks that he is not good enough for you . You were confused when he said that. You told him that he was good enough for you.