It's easy to have a moment of weakness and do something to hurt the man you love. You feel terrible and wish you could change what you did, but it will be too late and your boyfriend may have lost trust in you. The only thing you can do is hope that you can make him understand that you didn't do it to hurt him. He might not take you in his arms and forgive you right now, but with patience and taking the right steps, you can get your ex boyfriend to trust you again.
First of all, it is necessary to tell the truth. Lying about what happened will just make it worse when your ex finds out the truth and he may decide that he can never trust you again. You can't try to make it seem unimportant because to your ex boyfriend it is very important. Get it all out in the open no matter how much it hurts him. It is better to get it all over now than having details you withheld come back to haunt you later.
Don't make excuses or blame someone else for your actions. Try to stay calm and no crying or begging. If you are going to get your ex boyfriend to trust you again he has to also respect you. Making a clean confession and owning up to your mistake can go a long way toward making the man you love want to be with you again. You may feel that you are under constant surveillance, but you must be accessible to him at all times.
This is especially true if the mistake you made was cheating. It will have to be clear that you are no longer seeing the other man because if you slip again, you can kiss your relationship and ex boyfriend goodbye for good. Always let him know where you will be and that your cell phone will always be available to him. This might sound like being in prison, but you made the mistake and if you want your ex boyfriend to trust you again, you have to pay the penalty.
The other big mistake that can ruin your boyfriend's trust is lying. A small fib can be easily forgiven, but if you have lied to him about your past life it can make him question whatever you tell him. He could ask you to show proof if something you tell him sounds a little strange. You will have to swallow your pride and understand why he mistrusts you. After all how would you feel if the situation was reversed?
Of course the best policy is to be honest in all of your dealings, but you are only human and subject to temptation. You never think you will be caught, but when you are the price of regaining trust can be high. However, if you love him and really want your ex boyfriend to trust you again, swallow your pride and do your punishment.