My other half has problems/issues talking on the phone and that includes phone calls to me. Your mother should respect your feelings towards phone calls. I definately think setting boundaries is a good idea, my partner calls his parents once a wk. Any other phone calls that have to be made are done via myself. I know his mum especially likes to hear his voice, she like most parents can tell a lot from the tone of voice etc. If your mother continues to try and lay guilt on you, you could use another of our communication tools. Because of my other halfs phone issues there are times when we are apart and he wants/needs to hear my voice but can't cope with the phone call; so i use the the phones video to record a brief message ( i never video my face when talking; my issue ) and then i just send him that. Whatever you do, make sure you are the one is the driving seat. Your mother will just have to be grown up about it big hugs