One can understand why you are getting these thoughts as you have had been in relationship for the last 8 years and the girl has cheated you. If she is still physically involved with both of you she must be an unethical person and cannot be truthful to you in case you patch up and decide to live together. Taking revenge on the other person doesn't make sense, he must be equally victimised as you are OR he must be taking advantage.
Either way, it is your call if you want to let go of the past 8 years and look ahead the next 40 to 50 years of happy new life or keep pruding and thinking of suicidal or murderous and spoil your happiness.
Consult a Counselling Psychologist for further help and move on. There are other things and priorities waiting for you. Your world should not end up with one unethical person in life.
Answered2018-03-01 02:10:58
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