In other words: Don't say anything that would hurt someone. We all have been at the receiving end of hurtful words at least once in our lives. It's not a fun place to be.
I've realized that not everyone sees a relationship the same. Each relationship is different. One person may see it as a bonded friendship where the other see it as an acquaintance. One person may truly be in love; the other just likes that person. Sometimes two people are on the same page. Get the picture?
The words we use towards others affect the way we feel. We feel better having gotten that "off our chest". The words we use towards others affect the way they feel. That is why we are cautioned to temper our words with love. Some people have a thinner "skin" than others and are therefore more sensitive.
Once again, it comes back to living a life pleasing to God - being a Christian! Choose carefully the words you use when communicating with others on every level, not just about what the Bible tells you. Not everyone out there is a Christian, but that doesn't negate our responsibility to be a Christian towards them. We are sinners, as are they. Their judgement will come as will ours. Walk the way of Christ in every relationship you have. Be fair, be impartial, be kind and be loving AND expect nothing in return. Do it because that's what we are commanded to do by Jesus! Love one another!!!