The entire problem with liberal thinking is, you assume collective social moral constraint is equivalent to government telling you what to do. Unfortunately, human beings are not always responsible, if they were, perhaps we could all live in a society without laws, where we could all decide what's best for ourselves. That is not the case, so we can't live in such a society without eventual collapse from moral decay.
We as a societal community, have an obligation and responsibility to set boundaries and establish our laws of order based on those boundaries. This collective moralist view is apparent in many of the laws we have today, and I don't see you proposing we abandon these. This indicates you do see the value in having some moral boundaries and limitations, and being responsible as a society, but the complaint you make is a direct contradiction to this principle.
I don't want the state to decide I can't operate a motor vehicle while drinking a beer. I don't want the state to decide I have to wear a seat belt while driving with my beer. I want to decide for myself... are you okay with that? Is society okay with that? Apparently not, because we have established laws against it. However, it is the same argument you are making.
What I don't want, as a Republican who believes in originalist views regarding the Constitution, is for 9 people in black robes, deciding what is best or worse for me. I had rather have a referendum on a ballot and allow the people of my community to make a collective moral social judgment on the issue. I don't want you and your liberal judicial fiat to decide for me!