Make haste slowly summarizes the attributes of a rescuer when applying first aid.

It means that he must apply first aid as soon as possible but he must also be careful so as not to jeopardize the victim’s life.  He has to do it fast but must know the procedure so that he can both save and stabilize the victim’s life.

if your boyfriend is cheating on you, my best advice to you is to dump him, he's only going to drag you down. and if you do, don't fret there's plenty better that know how to treat a person right. i mean honestly, the whole point of a romantic relationship is love, and if you love someone you aren't going to cheat on them. i do believe in second chances, but why would he cheat in the first place? i personally feel that if someone cheats, they ruin any chance they wanted/had with you. i wish you the best of luck with this, hang in there.