Yeah, Rajiv Gandhi got away with the 1984 massacre, and now Modi wants to repeat the same by coming to power. Both parties are crooks and won't leave any stone unturned to come to power, and then retain it in whatever way possible.
As an atheist and a secular humanist, I can never support a religious nationalist and a fundamentalist. Corruption is a major challenge, but even more so in the inter-mingling of state and religion. Congress is selectively communal, but hide under the pretext of secualarism, whereas BJP are open about their communal stance. When the opposition itself is such, the choices are very limited.
That is one of the main reasons why I wish to see a push for third-front. They won't win immediately, but over the course of time, even if they could somehow manage to get themselves into the opposition, it would be a far better political landscape than just Congress and BJP bickering over who wants to stay in power.