Slavery is wrong even if you're given a time period to eventually purchase your freedom. I would point out that the real devil here isn't just alimony or child support or court ordered costs, restraining orders, etc.
All of these are symptoms of one very real, very pernicious problem: government involvement in family affairs. Anytime you introduce force and violence (government) into family matters and empower one party with the full force of law you turn every petty dispute into nuclear war.
Think about it. If I am a woman I am legally empowered to destroy my mates life if he pisses me off. I can have him imprisoned at will, banned from his home, banned from his children, impoverished, and enslaved for my benefit (and my boyfriend(s)) benefit and I can force him to pay for it all and its all legal.
Think about how a man must feel to have another man move into HIS house, be screwing HIS wife, be abusing HIS children, and HE must pay for it all. This is a COMMON scenario and the USA has the gall to help this situation! It is a miracle that more lethal violence hasn't occurred.
In places like Saudi Arabia women are treated poorly so says the world because they can be sent away with just the clothes on their backs from a marriage. They will then get to see the children only 50% of the time and will only be entitled to a minor stipend. The world calls labels this horrific. Men have it much MUCH worse every where else in the western world and possibly the worst in the usa as america embraces prison far more than other countries.
Lifetime alimony is just a symptom, a minor symptom, of the government replacing the social institution of marriage and like everything else the government touches it has become a morass of politics and evil. Get the government out of marriage completely and the problems go away. Alimony by definition becomes an agreement not something mandated by some black robed whore backed up by the jackbooted thuggery of the state.