Continue to be understanding. Patient. Try to understand that he is going through some major changes inside as he works to make those changes happen. I'm guess-timating... but I'll bet that you'll be very happy in the long run by being patient.
Imagine being w/ someone and they went into a hospital to have brain surgery and we were shocked at what they were like after leaving the hospital.
Recovery is much the same way.... the difference is... people can't see our stitches! But, after we begin to heal -- they will definitely notice our recovery!
For me, recovery has been one of the most difficult things and difficult challenges that I've faced in my life. I know, that it's that way, too -- for many others.
Fear, anxiety, and thoughts of "what will tomorrow bring?" will keep us in everlasting bondage and it's so powerful, that it will begin to manifest the things that we fear most.
You may want to re-visit the "Fear" section of Step 4 on it... and have your fear removed. And, also "trust" that your Higher Power WILL take care of you always.
Best wishes for you and for your boyfriend.