I read a book called "Love Sick" some time ago. The main thesis of the book is that love has much in common with certain psychiatric conditions, e.g. obsessive compulsive disorder, etc. It was actually a pretty interesting book.
I suppose a shrink would say that a condition is unhealthy when it gets in the way of your life, and prevents you from functioning.
Two billion years of evolution have programmed and commanded you to procreate, and that programming does not really care about your well-being, happiness or comfort. For example, evolutionary programming does not care that child-birth itself is an incredibly painful process.
Some species of spiders kill and eat their mates after screwing. A praying mantis will rip its mate off his head and eat it after sex. A sea louse gives birth through a process reminiscent of the movie Alien. (Not very pleasant for the mother.) Salmon have to shlep all the way up some god-forsaken frozen river past hungry bears to spawn.
The evolutionary programming really does not care about your personal interests when it’s trying to get you to procreate any more than it cares about spiders, praying mantises, sea louses or salmon. It doesn’t care whether you become a wreck. It just wants one thing out of you. After it is done, it doesn’t care if you fall out of love, the illusion of attraction disappears, your mate gets fat and ugly, you dump her after 7 years, and the child support and alimony payments are killing you. It does not care whether the drug has worn off. Evolutionary programming will have done it’s job.
The only thing healthy about this process is that it is "normal", it is what you have been programmed to do, and the human specie will continue. Thus, it is "healthy" in the same sense that dying of old age is healthy.
Now aren’t you glad that you didn’t ask this question of a cynical person?