I think there are a couple misconceptions in your post. I spot two:
First of all, "deterministic universe" is and over-condition. All we're really talking about is human behavior, which, rationally should be deterministic since it seems to be based on brain function that is largely classical and in fact, decision-making can be predicted based on brain activity to good confidence in test situations (Libet was the first to do this, but there have been more experiments since). It's a growing sentiment in neuroscience that our behavior is deterministic.
Secondly, you wouldn't be prohibited from a particular path as if your history had already been written. Your beliefs and decisions are part of that deterministic process. The question isn't whether we make choices, we obviously do. The point is that those choices, feelings, and beliefs are deterministic: they're based on a combination of your biological and environment states and your biological and environmental histories.
Psychologists use a biopsychosocial model nowadays, looking at how all the different influences feed off of and can amplify each other and there's a lot of politics involved in this, too... because it has implication for drug addictions, correlations of crime with education, etc, etc.
So your reaction to determinism, I think, is a fatalistic stance. And fatalism is not determinism. Determinism means that we actually influence things through our actions. We can receive information and change for the better because of it (or the worse... if that's in our nature). If the universe was completely stochastic... nothing you do would seem to matter because causality would be much more fickle then they already are in complex deterministic systems.