I know there are some people who would say that half is better than none. But that assumes that “none” is the other option. I believe you can and should go for a completely loving and trusting relationship. My vote therefore, is for you to end this painful relationship where you are so often trying to measure up or pass some test. An important clue to what goes on is that he always comes up with a new test when you get close. He’s either afraid of the closeness or he wants to keep an upper hand. Either way, you end up scrambling. I’m also very concerned that you say that you are fearful at times — another indicator that this relationship is way out of balance.
As much as your boyfriend says he wants to change, he hasn’t changed enough in over four years for you to settle for what he offers. You deserve better. Yes, you are in midlife. But that only means you still have half your life to go. I hope you give yourself the chance to find someone who loves you and cherishes you and is 100 percent wonderful.
I wish you well.