Can depressed people feel happiness? Well it's a complicated answer but in general one of the main criteria of depression is "anhedonia", which is a difficulty or inability to take pleasure in things.💙

As happiness generally reflects a pleasure in life itself or in things happening to you, then the anhedonia would mean "no, someone with depression can't feel happiness", but as ever it's so not much black and white as shades of grey. 💙

The lighter the depression the more likely someone is to be able to feel happiness, the earlier the depression the more likely they are to feel happiness, and the longer a depression has gone on the deeper it is the more that person will experience anhedonia in all likelihood and be unable to feel happiness for anything other than short bursts of time.💙

Non-depressed people seem to experience happiness as lasting a while and tailing off whereas people who are in depression whether that's at the beginning or more seriously in depression will experience happiness and then it will almost immediately tail off.💙

The "happiness amplitude" (the degree to which they feel happy) will be reduced over time as the depression becomes more severe. So instead of a high peek of the curve of happiness and then it tailing off (normal), they will experience less of the height and a sharper tailing off as that happiness just disappears. 💙