I will say warmth in tone and phrasing is everything especially if your main communication methods are online and not in person. It's hard to say without seeing an example e-mail and I just wanted to say it's worth trying to look back and being honest with yourself as tone can really effect people.
My work is project based with many rounds of feedback and I work often with someone who communication style is terrible. Her blunt phrasing honestly effects my stress levels everyday and really grinds me down.
She will have dictated the entire project down to the final detail but if she wants a change (to something she previously asked for, directly) she will phrase it like this
'This is wrong, should be like this'
'This is weird, you've made it look weird'
'This is in the wrong order'
All of the above will have been completely executed exactly in line with her last request.
She cannot seem to distinguish every time difference between asking pleasantly for a change to something that she previously asked for (we only have to reference the last e-mail she sent) and phrasing it like we've just totally fucked up and not understood anything.
She is one who believes she is 'direct' and a 'straight shooter' but she just comes off as really bad at her job and she can't seem to communicate anything appropriately.
That 'direct' tone - it really gets to you down day in and day out with someone speaking to you rudely and bluntly. It doesn't take that much extra effort to phrase things a little more warmly.
This is the difference.....
'Hmmm that's not quite what I envisioned - here are a few suggested amends of things we can try out so see if that makes it feel better'
'I'm not sure that design is really working for me - can I make some changes to the brief?'
'I've changed my mind about the order - can we swap a few things around and try them in different places?'