I think unconditional love is OK, it is the unconditional commitment that will do a person in.
Codependency is based on a toxic mix of conditional love and unconditional commitment. In a healthy adult relationship it’s more the opposite way round, that is love is unconditional, while there are, as there should be, clearly stated conditions related to maintaining a high level of commitment -- From "Growing Awareness" by John Bligh Nutting. This guy wrote The Fable of Two Codependents which I've read many times because it so accurately reflected my relationship with my xah.