I believe there has to be alien life forms out there, but ones that have gained the ability to reason and have the intelligence we have is actually said to be probably extremely rare. Most are either bacterial or just random creatures. If there are any out there trying to reach us, any signals we receive or send out will probably reach us or them long after we or they are gone. The chances of any actually reaching our planet physically is almost nil. Basically we aren't alone in the universe but we will be alone for the rest of our days without ever knowing the actual truth, is what I am saying.
Our universe is like going to any beach. It is said our galaxy is like one grain of sand in that whole beach and the distance between each granule is almost unfathomable. If any creature or some sort of spaceship can withstand the coldness of space let alone the time it takes to get here, they deserve to take us over. Even if they can travel the speed of light, which they would pretty much have to break themselves down into atoms (then have a machine that can put every little atom back in its correct place), it would still take hundreds of thousands of years to reach us and that's from the closest solar system as a starting point! Face it, we will not be, and have never been, physically contacted by anyone outside this planet
Roswell didn't happen and Area 51 is just a place where top secret, unpublished weapons are being tested. They have to be so secretive so other countries don't get the heads-up and start copying such weapons