But you'll worry anyway, as your anxiety is a product of your biochemistry, which is governed by deterministic processes.

It makes absolutely no difference if you think about it. It's not like choices are made for you even if the universe is determindric. If the world is or isn't deterministic it's not like anything would meaningfully be different - things would still be unpredictable to us. In an indeterministic universe randomness would play a part in outcomes, but that's worthless to us. This meme is about choices anyways, randomness or determinism doesn't matter in the end.

First of all is determinism not proven and may be/get disproven by quantum mechanics.

Second of all it also validates your suffering because it's seen as a determined thing to happen so that may give you some solice.