We are afraid of other people's reactions. Being truthful doesn't mean being insensitive to others' reactions. Tact is a virtue, but letting fear prevent communication is not. I told them once before. You may have sent the same message before, but sometimes people just don't hear.
Reminders can be useful.
You can never know for sure what someone will do. Do not allow what you imagine the other person might do stop you from communicating. If you have fear or some other consideration about sending a message, be aware of it. Realize that you can communicate even with your concerns. You can even choose to make them a part of the message.