The Role of Dopamine in Stress Responses

There are two types of dopamine cells, the dopamine value cells that show increased release in response to pleasurable things. And another type called salient dopamine cells which respond not only to pleasant events, but also to negative ones too. You can get this huge flood of dopamine when you've had a bad experience. The thing is, all of this sounds just really harmful and detrimental to the brain overall. So I wondered why would we have evolved to have these kinds of reactions in the first place? Life is stressful for all beings on earth, especially if you're somebody else's lunch. It makes sense that these would continue from species to species.