For me, the existentialists are important critics of 'absolutist' claims, and Heidegger and Merleau-Ponty are, at least in their later writings, also exponents of a doctrine of mystery: Being or the 'well-spring' of everything is, for Heidegger, ineffable, just as what Merleau-Ponty called 'Flesh' is for him.
When we want to reach a dream for the second time, you want it to come true, when you try so hard, you are so close to achieving it, it makes things very difficult to live with afterwards.