It is possible for someone to have trouble achieving erection during sex, but still be able to masturbate successfully.
However, it may well be too much masturbation that is making it difficult for him to gain an erection during sex. Get too used to one thing, get too dependant on it, and you can lose interest in anything else.
Regardless of this, it is completely unacceptable how he is treating you. It is unacceptable that he hasn't made much more effort to address this. It is not OK that he doesn't seem to be trying, or even showing any interest, in doing anything to change the current situation. To be honest, I have to conclude that he is not in the slightest bit interested in having a sexual relationship with you. You've tried twice, in three years? That's not enough effort from him, not at all.
Why is he not interested in having sex with you? I have no idea, I don't know enough about the situation even to guess.
If you really want to fix this situation, you need to take a bit more initiative, or nothing will happen. Either you need to keep reminding him to arrange that couselling session, or just go ahead and arrange it yourself. You need to make it totally clear to him not only that you are seriously unhappy with the current situation, but that you will leave if he does nothing to change it. When you tell him that, you need to mean it. Are you really prepared to live like this for the rest of your life? If not, you must be prepared to leave, and he must believe it. Sometimes it will take a threat this drastic to provoke a man into making any real effort to change.
Frankly, many many women would have given up and left long before this, particularly having been told that you "don't do it for him".
You definately need to get some counseling for the two of you. What he said is quite cruel in my opinion. I dont know enough about your relationship or the circumstances behind your marraige.
The fact that he has not contacted the counselor is not surprising. The things you have described are probably very difficult topics for him to address so he is consciously or unconsciously avoiding it.
I think if you are serious about saving your marraige you need to tell your husband that you plan to make the arrangements with the counselor. Ask him to confirm the times / dates that he can make it so that he does not have an excuse to miss the meetings.
He may miss the meetings or be late anyway, but I think you should go anyway; with or without him.