When I came out as asexual to my cousin, he asked what it meant, listened carefully, and said that since he couldn’t imagine not being straight, I couldn’t be asexual. When I came out to my best friend, she told me asexuality wasn’t evolutionarily advantageous. When I came out to my brother, he just worried that I might take longer to find a relationship and feel lonely in the meantime. When I came out to my mother, she said that explained why she hadn’t been able tell if I was gay or not. I still talk to two of the four.
Really, it’s all been pretty anticlimactic.