What is realised in my history is not the past definitive of what was, since it is no more, or even the present perfect of what has been in what I am, but the future anterior of what I shall have been for what I am in the process of becoming. - Lacan, Écrits, P. 86
Is not Lacan’s future anterieur his version of Marx’s Thesis 11? The repressed past is never known ‘as such’, it can become known only in the very process of its transformation, since the interpretation itself intervenes in the object and changes it: for Marx, the truth about the past (class struggle, the antagonism, which permeates the entire past history) can become visible only to a subject caught up in the process of its revolutionary transformation […] The key point not to be missed here is that this moment of future anterieur is not the moment when a past situation is ‘defrosted’, caught in a transformational dynamic, but, on the contrary, the moment of ‘deep freeze’ elaborated by Walter Benjamin: as Benjamin emphasized in his Theses, the present appears to a revolutionary as a frozen moment of repetition in which the revolutionary flow is immobilised, and past and present directly overlap in a crystalline way.Slavoj Zizek, The Plague of Fantasies, pg 115
The point I think is that how we relate to our past is the condition for the person we are in the process of becoming; in coming to be someone else, the past itself changes in that it is revealed as something other than the definite events we took to precede our present situation. There was something deeper, murkier, ambiguous in those events which we couldn’t identify until we became the person we now are, suddenly recognising how what went unseen (or even disavowed) created the possibility of becoming someone who could change.