How to prevent self-deception?

I have recently attended my first Vipassana 10-day course. I observe the moral precepts fully, practice diligently and attempt to proceed wisely on the path. I came into contact with Vipassana because of my ex, who, both in showing me to the path and in harming me, has been my precious teacher. In harming me, in failing to observe the fourth precept and sila, in seeking passion as a distraction from his suffering and a confirmation of his ego, without apparently being aware of this and even if being aware, not changing his behavior, my ex has caused me concern with regard to my own attempts at leading a proper life. I know I am not in a position to help my ex, as he has harmed me (also, I tried and he reacted with hostility), so what I am left with is the striking fact that this amount of delusion is possible in someone who calls himself a serious Vipassana meditator, which worries me with regard to my own practice. If someone who has been practicing for over 10 years thinks they are aware and are everything but, what am I going to do? I have fled into passion as well, in a quest for distraction from suffering as well as from a need for guidance and affirmation of my own ego. The obvious answer is to truly feel and accept painful feelings without reacting by fleeing into passion. But these impulses are strong and the mind is clever. What can I do to prevent this behavior? Can there be a mistake in the meditation practice itself that causes such obscurations to persist? Additionally, I do hope to find a partner who observes truthfulness towards himself and others. How do I go about avoiding the blinding capacities of passion and idealistic desires in judging any such “romantic" situation accurately? I imagine working on one’s own mental and emotional hangups will diminish obscurations — how is one advised to go about this other than meditating? I know these are big and difficult questions. Any and all input is appreciated.