I think it would depend why. If it was permanent, we were unable to have any (more) children (age, illness, or whatever reason) and for the sake of holiness, I might be willing to - but only after we had fulfilled the purpose of marriage as fully as we could. If one of us had a medical condition that prevented sexuality, I would be fine there, too. We are already abstinent for periods of time using NFP - though we're talking about changing that soon

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On the other hand, if my husband couldn't give me a good reason why - I would feel very hurt. Sexual intimacy is very important to me, and if I didn't understand why, it would feel like he was trying to "take back" his marriage vows and that he didn't really think of us as one flesh.
Essentially, it comes down to emotions and fulfilling the spiritual purpose of marraige. While the physical satisfaction is great, it's the emotional and spiritual satisfaction of renewing our wedding vows that is important to me. Including the promise to accept children lovingly from God. I really want to get to work on that one

But if there was a good reason for long-term abstinence that didn't seem like a rejection of me as a sexual being and that fulfilled the purpose of marriage as much as possible under the circumstances . . . cuddling is absolutely wonderful, kissing is great, chocolate for me is a bonus, and I'll give a back massage in return. Add some praying as a couple, and that sounds like a dreamy evening.