It can be very, very difficult. It is not, by far, an exact science for a person or for a mental health professional. I suffer from depression but have also lost both my parents and I was very close to both of them. It was difficult for me to separate, sometimes, what was real grief and what was depression. There is this weird opposing tendency in our society to both minimize and trivialize real grief and honest sadness and to treat every episode of grief and sadness as though it was some kind of pathology, some kind of disorder, that needs medication.
But @Mariah both @Kardamom and @augustlan make good points, Kard’s mental check is pretty good though some tough situations interfere with daily life and relationships, my grief did that, and Auggie’s comment that if you are at the point where you are asking, if you have gotten to point, whatever your issue is, that you are wondering if it might be time to see someone then it very well may be and you probably should. A profession would at least be able to assess your situation. Life is very hard and very sad sometimes and medication doesn’t and can’t fix that and I’m not sure I would want it to, your heart can only be broken if you are capable of love, but if talking to someone or taking medication can help in yours or mine or anyone’s circumstances I’m all for that.