About the concern over you "hurting yourself": Is this a new thing? Or has he always been like that?
Perhaps he thinks he recognizes that you are doing this for his sake, which arouses guilt and resentment that he doesn't want to deal with.
(I say "resentment" because he may now feel that you "trying" in this way means that he "owes" you something. Someone also made a note somewhere about how positive changes you make sometimes angers your spouse - I think this is in either the DB book or the DR one.)
If you really think you'd get something out of it, it might be a good idea to go ahead with the course. It will probably make the point that you are going to do what YOU want to do, and that you feel that you have the right to do so.
