What's wrong if I check Instagram or Facebook to distract myself from negative thoughts & emotions?

A participant in a Mindfulness workshop asked me this question. The problem is that when you do that, you are not addressing the issue at its roots. For the time being, you are suppressing the pain. So the call for action is not to distract the mind but learn the tools to handle negative thoughts. One does this in a meditation practice, where we train our minds to witness the thoughts without getting carried away. Doing this, again and again, helps us understand the nature of thoughts. The capacity developed in the meditation to acknowledge and let go of our thoughts comes to our rescue when we have thoughts of fear, anxiety etc. Now we won't need to distract or engage the mind in anything but bring mindful attention to our thoughts, see them come in, stay for a while, and then leave without being affected by them.