Why do humans have needs?

Is it solely to feel good or for a greater purpose?

How do I tell you that I've been supressing all my needs and I'm on the verge of another depressive cycle.

It seems to me that few people live their lives in such cycles. It's like a rollercoaster ride that I would prefer to do without. I know of such people who live in cycles of boom n busts. I'm one of them myself. In that sense, I identify with and empathise with others who seem to be blessed with happiness at one point of time and the next they fall into the hole of endless despair.

I wished I could do without such emotional needs. Life becomes harder to handle.

Sometimes I even imagined rationalising everything, including irrational emotions.

It's like a darker side.
A hidden evil waiting to be subdued.