If he wants to marry the mother of his two children, he can give up his rights to be Terri's legal guardian, and then go for a divorce. It's not impossible to go before a judge to move guardianship rights, if he really wants to wash his hands of her and move on with his life.

You're right, there are so many factors that make it impossible for us as outsiders to know what's truly going on, but there are other options for her. She has two loving parents who are willing to shoulder her responsibility. It takes a very strong person to give up their life to help take care of a loved one... They should have that right if they are willing to face all the consequences involved. Terri will probably never get better, but she shouldn't be starved to death just so the husband can go on with his new woman and their two kids with a less burdened conscious.