Youâve asked two good questions, so let me take the âwhyâ first, because understanding it often eases some of the distress.
Guilt is meant to be useful. Itâs the mindâs signal that something matters to us and may need repair. Regret, though, often uses hindsight: we judge a past decision with information we didnât have at the time it was made. Thatâs why it can feel so harsh.
Night hits harder for a few reasons. During the day, work and people keep the mind busy. At night, the distractions stop, youâre tired, and your ability to manage emotions is lower. So the mind replays the same thoughts again and again; this is called rumination. Crying or shouting to yourself is your body trying to release that built-up pressure. Itâs understandable, and it also tells you the feelings need a better outlet.
Next Steps
Set aside 15â20 minutes in the early evening as âreflection time.â Write down the decision, what you knew back then, and why you chose what you did. If a thought comes at night, tell yourself, âIâll look at this tomorrow at my reflection time.â Ask yourself whether anything can be repaired, such as an apology, a conversation, or a change going forward. If it can, plan one small step. If it canât, the work is self-forgiveness rather than fixing. If this has gone on for more than a few weeks or affects your sleep or daily life, consider a few sessions with a psychologist. Guilt and rumination respond well to CBT and compassion-focused therapy.