First of all I want to say that each language is beautiful and unique!!!
   The distinction between Russian and Belarusian languages is essential: in an alphabet, in grammar, in phonetics, in a dictionary, etc.
   In my opinion Russian and Belarusian are comparable with Italian and Spanish. Languages have an Common Slavic basis as Latin is for the European languages. However Russian and Belarusian developed absolutely separately. I think Belarusian is closer to Polish and Ukrainian than Russian. First of all languages have a lot of similar words. Then Poles, Ukrainians and Belarusians (provided that they speak Belarusian) understand each other very well while Russians understand separate words. This fact conveys a great deal. Example from my work: the Polish drivers always asked to speak Belarusian because of the best understanding.
    And some words about trasyanka)
    Trayasyanka is Russian with the Belarusian accent and inserts of Belarusian words. IT IS NOT THE BELARUSIAN LANGUAGE. Unfortunately the greater part of the population speaks trasyanka.
But I know many young people and cultural figures who speak Belarusian at home and at work. I would be glad if more foreigners began studying Belarusian. I hope you will come to our country and will see what a friendly we are))