We live, with the aim to do the best. Live it the best way so that we will not regret. We were given ability to think hence we can justify our options, make informed decisions, be prepared for the foreseen consequences.
Therefore, please do not mourn over the adverse consequences of wrong decision that you have made especially when you do it consciously. You just shouldn't because you have chosen it. It was you who decide. If you knew you can't bear the consequences why did you adopt the decision? You decided to stand for something, so be brave. If you don't think you are not that strong, which you will be; than please do things right, humbly right. Consulting ALLAH, the believers and your iman; putting aside was was of syaitan and desires of nafs.
Whenever you did good, it was to your own advantage; and whenever you committed evil, it was to your own disadvantage... (Isra:7)