I do the same as Lisa T. I use the cup more than once.

We reuse our glass drinking bottle

Install a drinking fountain spigot on your faucet then you don't have any cups or germs to contend with....

I use the paper cups but I reuse my cup for a few days until it gets mushy.

So, what you are really apparently blithely saying is to proximately promote the spread of germs with a reused glass rather than avoiding it through single-use cups for the remote goal of "saving the planet"--whether or not YOU are actually saying this, I think this is the problem with a lot of the recycling mindset.