I actually do know how that feels, katchie....I'm still close to my former MIL. It's hard that so many people get hurt.
In time, and with practice, that automatic need to answer when the phone rings will turn into looking at the phone to see who is calling and then continuing on with what you were doing. I know you can't turn the phone sound off in case it is one of the boys, but your ability to just look and not answer will improve!
Hang in there!