Hi Jolana -- I live in the Michigan Upper Peninsula, so pretty much cold, colder, coldest would describe the growing conditions here...
Two winters ago we had an unusually horrendous winter, with extended periods of sub-zero temps, but the little tree came back pretty well last summer (although again it was quite late to break dormancy). This past winter wasn't nearly as cold, pretty moderate for us really... but I'm kind of wondering now if the redbud was so stressed from the last winter that it's about to give up.
