Are you currently dating someone? Are you honest with them? I mean really honest with them? If you have been in a relationship with someone for a period of time it is best to be as honest pas possible before you even consider marriage. Any hidden secrets or a previous relationship is not the best way to start a marriage.
If you really love someone then you want nothing in the world to stop you from being with that person. Perhaps you kissed a girl just before you stared dating officially. Is it wise to tell the person you are with now. I really think that this is the best time to come clean.
However, as with all things it is very important that you approach this the right way. If you felt nothing for the girl when you kissed her then tell her that now. If the kiss did not mean anything then it is better to be open and communicate that fact. Communication breakdowns are one of the principal reasons why relationships fail. Not being honest is part of the communication gap.
I have seen time and time again when people have not been honest and forthright with the person they are with and it always ends up in disaster. After all you are talking about potentially spending the rest of your life with this person do you really want to begin on the worst footing?
Do you want to avoid that breakup or divorce? Then it will take time and being honest with each other. Honesty in the relationship is key to happiness. Do not begin to think about marriage if you cannot be honest with the person you are with now.
If you are experiencing problems because of a lack of honesty in the relationship the best time to change is right now. You need to have the tools necessary in order to do this right. Learn from those who have been through this before.