Think rationally here... They want you because of how wonderful you are but are too stupid to treat you in a manner that you deserve... Why give second or third chances when there's someone amazing who deserves a first? Don't allow your heart to be broken by a player, you deserve better!
No trust me from personal experience. Once some body cheats as much as they tell you they will change and not do it again they are lying because ones it happens it's makes it easier for them to do it again next time knowing they will be forgiven