I will take this post at face value and respond with some thoughts, just musings:
You are approaching 20. Let us assume a life expectancy of 80. If you do something retarded that fucks up your life, you discard the potential that within the remaining 75% of your life, a solution is found or you may change your mind, which has apparently happened before. Thus, do not do something retarded.
You call the positives "false hopes" because there appears to be an expectancy that a state of permanent happiness is the correct, the "right" end result. Do X steps and you will be satisfied forever. This is not the case.
Consider instead the nature of what you describe as "the loop". You may find it reflected in the phrase "This too shall pass" - in prolonged despair remember that it cannot last forever: It too shall pass; and take solace in this.
However, when you are happy, during times when what you call "false hope" is there, remind yourself: It too shall pass; And appreciate these moments all the more. It would be absurd to then fall into despair, it would be akin to crying as you are eating delicious cake just because at some point, the cake is done and there is washing up to be done and new cake to be baked. Enjoy the cake, dipshit. It too shall pass.
If determinism is real, then it is irrelevant whether you despair over it, or are overjoyed over it. You can discard responsibility and do bad acts from this perspective, but it will matter no more than if you do not - as such, you might as well (pretend to) take responsibility and be a good person, for it will make you feel happier.
Precisely because perhaps, it is all a dark, a largely or entirely predetermined, an uncaring universe - we must do our best to light a candle ourselves and for others if we can, rather than impotently curse this darkness.
TL;DR: Don't shoot people or kys you retard. Go eat delicious cake with someone.