Adultry and mental torture

my husband has been in relationship with our neighbour's wife for years who is a wife of his best friend,but unfrtunately he has died,before his death he sent sms to my husband about all this ,I used have strong feelings that he has an affair as he normally used to away from house and i myself found him carrying protection packets in his office troussers,and one day i even found one strange message saying "Iam waiting why you have not come,you r showing me attitude after all this has happened" Even some of my neighbours saw him visiting him to her house and staying there for long hours in the absence of her husband, when i try to talk with him he simply ignores me and says people and u r all lying .Idont know how what exactctly to do but all this has broken me emotionally,ihave through mental pain which is not visible but i often find myself drowning it and and losing my intrest to live this life more .i often ask god if he ever can help me in getting the justice or he should take my life now which i donot find any worth to live