At some point you will be affected by a challenging moment (as all of us are); a physical pain, a bad mood, or perceiving another as a 'terrible person'.
It can be helpful to see if you are building the suffering around this moment by asking the following questions.
1. Am I aware of this? - i.e. do I know that I'm in a bad mood. Can I open to it, can I be with it, soften around it?
2. Am I adding suffering by ruminating? - Am I cycling through my story again and again of the past (e.g. feeling 'hard done by'), or the future, that is building the suffering?
3. Am I overidentifying? - i.e. "I'm in a bad mood and this is my personality, no one else is grumpy here." - this contracts us adding to our sense of suffering.
Bringing awareness to the above already offers us more space. Consciously putting down unhelpful thoughts stops the process of building up our suffering. Adding in a kindness practice (lovingkindness or self-compassion) frees up the heart for more wholesome states.