Healthy self-care involves not compromising your personal well-being, your values, your principles, to feed another's addiction or illness. It begins with resolute awareness that the other's sickness is not your fault. You cannot cure it by subjecting your self to the threat of psychological, emotional, and physical abuse at the hands of a lost, addicted person, even if he or she is your spouse. Keeping clear on these fundamental truths are crucial to your sanity.
In addition, healthy self-care includes seeking help. If you're trying to handle it on your own, don't. Part of self-care will involve appropriate support from others. You don't need to face it alone.
"If you love someone who lies or is deceptive, then one is not loving by trusting him or her." (Dr. R.D. Laing, psychiatrist/author)