You better give this some more thought, INSIS.
Women are evil? Get a grip, INSIS. Women are people. Like men, they come in all flavors, shapes and sizes.
Visualize female sexuality as distributed along a line. The right end represents women who are asexual. They don't need it or want it. If they never have sex in their lives (with others), that's fine with them. The left end represents women who are highly sexual. They need it, they want it, it's never far from their minds, and they pursue it. Successfully. They have *many* lovers. Visualize the midpoint of the line as representing average (median, if you prefer) female sexuality.
Now, visualize male sexuality as similarly distributed along a line. The right end represents men who are asexual. They don't need it or want it. (BTW, this demographic is roughly 1% of men and women, apparently -- check Wikipedia.) The left end represents men who are highly sexual. They think about it all the time, pursue it relentlessly, and have *many* women. Visualize the midpoint of the line representing average (median, if you prefer) male sexuality.
Now, consider a man whose sexuality is somewhere right of the "male centerpoint," while his woman's sexuality is somewhere left of the "female centerpoint." She will, most likely, seek and probably find sex outside their relationship (/marriage), with or without his knowledge. She needs it and her need is legitimate; he doesn't provide it because, well, he can't. He isn't built that way. Due to various social and economic constraints, however, she may not wish to divorce him or break off their relationship. For similar reasons, he may not wish to separate from her. They may, in fact, love each other. So they live as cuckold and cuckoldress. There are *many* on this forum who consider that a highly erotic form of relationship and a desirable way to live. There are many other couples throughout society, presumably, where the man is a cuckold but does not know it, or he knows it and does not like it but quietly accepts it.
Regarding your thoughts of "terminating" your rival: I didn't see anything in your post I could identify as evidence. Do you know your woman is fucking him, or do you merely suspect that because you see them talking and spending time together? If you act on your dark thoughts, what is the probability you will have murdered a man for no reason at all?
In any case, lovers and/or spouses are always the first suspects in murder cases. You may think you can plan and execute "the perfect crime," but almost certainly you would be arrested, charged, tried and convicted sooner or later, if not immediately.
Another consequence you might envision is losing your woman immediately and completely. In threesomes, murders have a way of destroying the remaining twosome. Women, like men, have "intuition." She would strongly suspect you of being the murderer, even if she didn't see you do it.
Then, having lost your woman, you might envision being destroyed economically by the ensuing legal actions and trial. (Trials are nightmares.) You would then be destroyed in the deepest personal sense imaginable as you spent the rest of your life in prison.
As you know, on television all problems are resolved in 30 minutes, often with a shooting. The "bad guy" is dead (instantaneously) and the "good guy," holding his smoking gun, feels vindicated as does the viewing audience. After several commercials, the show is over. There are no messy investigations, trials, and catastrophic personal consequences. Real life is not like television.
Your feelings of extreme jealousy, accompanied by thoughts of murdering your rival, seem expressions of a strong feeling that you "own" your woman friend… like your refrigerator, or your car. But you don't. She is her own person. She has her own wants, needs and desires and, to put it bluntly, she owes you nothing. If she has favored you with her friendship, and even some sex, you should appreciate that. You have gained much. If she has begun fucking another man, you should view that as her right and prerogative, because it is. It is not your place to take, or threaten to take, some sort of violent action in response. Not against him, and *certainly* not against her.
As for byebyeduckie's suggestion that you shoot your rival in the knee: it's no good. For one thing, shooting someone in the leg (if you miss the knee) can easily result in severing a femoral artery, leading to rapid death from massive blood loss. If that didn't happen, he might come after you later (on his artificial leg) and return the favor. In either case, you would immediately and permanently lose your woman, as I mentioned above. And in either case, you would find yourself economically and personally ruined by the ensuing investigation, trial and prison sentence... all accompanied, very likely, by permanent loss of your means of earning a living. Visualize your self in hundreds of job interviews, attempting to explain to potential employers why they should trust you with employment when you were convicted of crippling someone by shooting them because of a romantic disappointment.
What’s happening to you is a minor lesson in the school of hard knocks. Later there will be others that will be more serious — perhaps a lot more serious. You better give this some more thought, INSIS — a lot more thought, and get your head together. -- Custer