The words we speak often times reflect the mood we are in.
Bad mood however plays a more significant role in the words that come out of our mouth. We tend to be more aggressive and spiteful when in a bad mood especially when this mood is caused by a person close to us. Everyone near us at that particular moment therefore may be in line of hurtful words.
Truth be told, yorubas (where I come from) say 'eyin lohun' which means words are like eggs, when it drops, it breaks and you cant pack it back. When you say bad words to others because you are in a bad mood, it disrupts the image the person may have about you.
Therefore, no matter what, do not mix bad words with your bad mood because you would never get the opportunity to replace the words you spoke. Words said when in a bad mood can hinder the favour we deserve long after we have switched back to the good mood.
Wish you luck in your relationships!