Do you still think we are alone in the Universe?
Why do you assume that your potential interlocutors believe this?
You miss at least a couple of signal points here. If you are sitting in your house, and i am sitting in my house, and we are miles apart, then it is reasonable to say that you and i are alone. Now, if we had a telephone or a radio, we could speak, and to that extent, we would no longer be alone. However, it the time it took for one of us to speak and that message to be received at the other end exceeded our life expectancy, then we would be, functionally, alone once more. If someone lives on a star sixty light years from our planet and i send out a message, even it received and replied to, the likelihood is that i won't be alive when the reply comes in. Were humns ever established on Mars, if you got on the radio and said "Hello," you'd have to wait 40 minutes to get a response. Conversation would be difficult at best. Over intra-galactic distances it would be impossible. You could send a message out into the void, but it would be silly to expect to converse. So, yes, we are alone.
A better question would be, are we unique. That might be worth discussion, in the sense of are we the only sentient, self-aware, technological civilization.