If you seriously believe that, why dont you kill yourself?>I do not see any valid refutal from you pertaining that everything is built on suffering.
I can go outside and walk through the countryside and I see cows standing in the sun and eating grass the whole day. How is that built on suffering? Because one day they might get sick or get slaughtered? Why should that make everything before worthless?
Do you think nobody on earth is truly happy with their life? Maybe you should make an argument how "everything is built on suffering" first.
Freedom, justice etc arent subjective. The idea of freedom exists independently from your consciousness. You can discover it, but you cant change it or destroy it. A better example might be pi. It has the same ontological status as freedom or justice, its an idea, not materia, you cant touch it, you cant destroy it, it exists independently from your consciousness, but it is nonetheless real and not subjective.
Get a teacher or good secondary literature and start reading Plato, slowly, start with Alkibiades 1 and reflect on the relationship between teacher and student and on the different types of not-knowing.