Change requires change (sometimes a lot; sometimes a little).
But what does that mean, exactly? Well, it means a lot of things -- different things to different people. If you don't like something about your life, change it. This could mean physical change, environmental, or purely psychological. You may think that, in whatever circumstances you are currently in, that your life is spiraling out of control and you're powerless. You may be able to change or make the situation better somehow; you may not. Maybe there's nothing you can do. The one thing you can always change, however, is your attitude and how you think about it.
You might think it's hopeless and there's no point in trying anymore, but sometimes you just need to have faith that everything will end up working out. Sometimes it's about changing that, "it's never going to get better" into "Everything will end up working out" and "It's going to be okay." Or if you just can't bring yourself to believe that it's going to be okay (because that happens probably more often than not), try telling yourself that you don't know what the next day will bring and find comfort in that. It may be better, or it may be worse -- You don't know.
Sometimes the change is as simple as turning your negative mindset into a positive one (or maybe just a slightly less negative one).
Because the situation may be terrible and bleak, but your mindset doesn't need to be. And even though having faith alone seldom changes or magically fixes the situation, at least it can help keep you calm and maybe think about it from a more realistic perspective. Maintaining a semi-positive mindset probably won't change your situation much because change requires way more than positive thinking, but a negative mindset sure as hell won't either. Your change may require a change in environment, career, lifestyle, routine, a lot of different things -- but most importantly, in mindset.
A better mindset has a slight chance of making the situation better, but a negative mindset has zero.
This isn't always easy and you will slip up one, two, twelve times, but the possibility of a better tomorrow is worth it.