It's probably been damaged by dessication from high winds, and possibly by the cold snap, but I don't think what you described is bad enough to have killed it. The root system of Black bamboo is hardy to 5F. My only concern is that bamboo in pots are not as hardy as when they are in the ground, and I don't know if the windchill factor is a further issue. In any case, don't give up yet. The culms that have become "light colored" are dead or dying and can be trimmed back. I suggest you put it in the ground this spring and make sure it is kept moist. It would be best if you can plant it somewhere it gets decent sun, and is at least partially sheltered from the wind. You should get some leafing out this year (although it may be a little sparse). You may not get any new culms coming up for a year or two...but that is normal for bamboo when they go from a pot to the ground. I'm in Zone 8 in the Seattle area, so my conditions are somewhat similar to yours, although one Zone warmer. My black bamboo stay green all year, but I have done some transplants in the past that completely defoliated from the shock and it took months before they made a comeback. Good luck.

Thank you for the quick response and excellent information. I will spend some time preparing the planting site and get this bamboo in the ground as soon as possible, as spring is definitely coming soon to Southeast. The site I have chosen is windy, but then so is every other spot in my seaside yard, so I will screen it from the wind with a heavy glass door that I happen to have available for garden purposes. Keeping it moist is never a problem when you live in a rain forest, so at least that won't be much of a problem. Hopefully the plant is strong enough to come back. I will monitor and report in a few months. Thanks again.

Good luck. I will be interested to hear if you are successful. Even if you aren't, your micro-climate can support a hardy bamboo in the ground, so don't give up, even if this one doesn't make the comeback I am hoping it will.