Before getting on to the answer of this question, let’s see what exactly the meaning of “alone” is.
Google defines “alone” as:
“Having no one else present, or on one's own” and “indicating that something is confined to the specified subject or recipient.”
If we see your question, keeping in mind these meanings of “alone”, I think you want to know, if there exists life anywhere else in the universe, except on Earth, or is the life on Earth exclusive?
Well, according to me, scientists will still take at least 25 years to find that out, and hence we just can’t neglect the possibility of other life forms existing in the universe. So no, seeing it macrocosmically, we are possibly, not alone in the universe.
Many organizations and technologies have come up in the past to research for other life forms, but they need some more luck. Search for extraterrestrial intelligence (SETI), is one of them. SETI’s project, Phoenix, was dedicated to this search and with great effect. But nothing was heard. For this search, sciencemag.org says,
“Phoenix, for example, scanned just one or two nearby sunlike stars out of each 100 million stars out there. For such sparse sampling to work, advanced, broadcasting civilizations would have to be abundant, or searchers would have to get very lucky.”
So the hope of not being alone in this vast universe is not yet faded.