Anarchists see the state as another system of class. A socialist state does not create a classless society, it changes the class dynamic from capitalists and workers to bureaucrats and workers. The workers themselves do not own the means of production and have to answer to the politicians and bureaucrats that manage the means of production.
And if that is your perspective then I do not see how anarchists and marxists could ever cooperate, as you said our goals are not aligned. Which is to say I do not see how you could be surprised by anarchists not trusting marxists. Doesnt sound like we have enough in common from your perspective to work together without one of us betraying the other.
Also no the Kronstadt Rebellion was an anarchist revolt, freedom of the press and speech for socialists including anarchists was one of the demands of the rebellion and so was bringing back the workers soviets that Lenin got rid of, among other things that, to me, are just asking for a more democratic and free system that doesnt centralize all the power to one party. The link I attached is the demands of the rebellion and it has nothing like you speak of.