I thought of something else that might help. You can say "It seemed to me that I was in your way in the shower and I let myself feel rejected and insecure." The use of the words "I let myself" lets him know that you take responsibility for your feelings. Why do this? Because if you put him on the defensive, he'll just clam up and you won't get anywhere.
See how it sounds if you put the shoe on the other foot-- if he said to you: "When you got in the shower I let myself feel anxious and inadequate." That's more likely to get a compassionate response from you than an angry one.
