Buddhism broke up my marriage
I don't suppose that any of us are qualified to advise you on your marriage or the optimal duration of it.

In theory, I really don't think it's fair to say that Buddhist love is non-romantic.  The Nakulamata Sutta (AN 4:55) is a perfect counter-example; it is a promise the Buddha gave to a blissfully married couple to be united again in the next life.  The text is certainly much sappier, I would say, than any Hallmark movie or Valentine card.

I would say that even with a complete embrace of, and transformation within, the Buddhist dharma, one still has whatever karmic obligations in this life that one had before.  Nobody can say, well, I wouldn't have accumulated this credit-card debt if I were a Buddhist, so now that I am a Buddhist I won't pay the debt.  And likewise a convicted felon will still have to serve a prison sentence, even after taking refuge; a recovering alcoholic will still struggle with health problems in the short term; etc.  Being bound to a spouse with wedding vows is a very mild form of karma, all things considered.

I would think that if you really are a Buddhist, than upholding the reputation of the Enlightened One, the Teaching, and (more to the point) the Community should be a much higher priority than your own purity and practice.  Would it cause pain, if you simply announced to your wife, "I don't need a wife anymore.  I'm a Buddhist now"?  Would it (somehow) make her more likely to take refuge and discover the benefits of the Way for herself?

I would advise that Buddhism, like many other non-mainstream philosophical movements or self-help doctrines, tend to attract seekers and people struggling for answers.  Even in the Buddha's own time, recent converts were regarded with a healthy skepticism.  If you really are growing apart from your wife, the reason is much more likely to lie within yourself than simply following the dharma to the letter.  Perhaps you feel that your wife is holding you back and lacks the potential to help you live your best life; and phrasing it as an issue preventing progress in the Buddha path sounds holier and gives you permission to voice your true feelings?

Again, you still owe some amount of fealty to your spouse simply because you took a spouse; but if you no longer feel "attached" then it's okay to respectfully discuss that with her.  But I would talk to a therapist first.