When happiness is seen as being a thing to have, own or be, then the chase is on and we are more likely to end in feelings of shame and guilt.
I'm not saying being, thinking or feeling happy is a horrible place to be. It is likely striving for happiness is not the answer when you already have it, we are able to live in all weathers of the mind and emotions. When we attempt to force the sun in a metaphorical storm anxiety and frustration prevail.
Be open to the fact that anxiety, sadness and disappointment are essential to the human experience. It is not a 'disorder,' that needs to be fixed, or cured it is acknowledgment that we pass through sadness just the same as we pass through joy, allowing our emotions to be the same but different.
Problem solving or fixing emotions is to deny the validity and undermine their purpose.
Emotions are universal and not some feelings being prioritised over another. Sadness, anger, fear belong to us all just the same as love, joy, and peace.