Is hope a good thing or an evil thing?

It can be used to manipulate yes absolutely however I will tell you this from personal experience to live without hope is worse than death because it turns you into The Walking Dead. Thus making you a very dangerous person

Remember, Red, hope is a good thing, maybe the best of things, and no good thing ever dies.

Your question is too general. While the image added by you circumstantial, making your question biased. Either you should expect a detailed subjective answer, or specify more details in your question. Otherwise people may think you are not clear/confused with the question itself in your mind.

At times in my life, it's been evil

Depends on the situation

Could be either, could be both.

Depends on on what it's in