Email is more helpful, in my experience. To be blunt, some of the people answering the phone shouldn't be volunteers.
It still hurts remembering the time I called extremely distressed and found myself I talking to a woman who sounded painfully bored throughout. And no, that wasn't a figment of my distress, I can interpret tone.
It caused much more harm to be trying to reach out to someone who was making it very clear she didn't give a shit. If I'd had other options I wouldn't have called.
There have been a few awful calls, which is why I generally avoid calling - it is not worth the risk of things being made worse. Although there have also been good calls, the harm that can be caused by a single terribly handled call cannot be balanced out.
If you're at breaking point, it's irrelevant that Jane down the road is having a better phonecall or that if you were still alive in a week's time to call again it might be better...
People who can't be arsed anymore or are burnt out (or just arseholes) shouldn't be answering the phones.