To be depressed sometimes and depression in mental health is two different things.
Since it often happens in the evening, do you think it is feeling tiered physically or mental stress?
If it is related to mental stress, You need to focus on what are the situations through which your emotions gets triggered, being aware of the cause makes it easy to find solution or cope up with the situation.
Next Steps
Try to do it on your own, if you find it difficult take professional help, a counselor or clinical psychologist can help.