Let's take romance as an analogy. In the early stages there is plenty of deception on both sides as we present our best selves. There's a fair bit of self-deception too, as our hormones kick in, the rose coloured glasses are firmly installed, and all our evolutionary drive is hurtling us towards coupling and commitment. It is not logical or reasonable, but we do it anyways.
That usually only applies to young naive and often inexperienced teenagers. Not mature, experienced and critical thinking persons. I mean when was the last time you 'hurtled towards coupling'?
Between blind love and blind faith I think blind faith to be the more dangerous.