Every person has its own strengths and weaknesses. At this point you need to know that some weaknesses cannot be ignored when you choose a person for a relationship or marriage. And if you notice some of these negatives in your partner, you should think twice whether it is worth to spend a lifetime with such person. You have probably heard that once a cheater, always a cheater.
That is why it is never wise to forgive the person that once cheated on you. If you forgive this person then that person will surely try and cheat on you again.
Another thing that is a deal-breaker when it comes to relationships and marriage is violence. Namely if your partner is violent and does not choose words when upset, ask yourself why are you still with such person?