I will agree with most of the other posters in this topic and say that you definitely need to come clean with your husband. If he seemed at least comfortable with the idea of you having feelings for another person, then a kiss or two probably (although you can never be sure) will not make him fly off the handle. You can probably discuss with him the reasons for keeping it secret from L's wife and see if he is willing to work with you so that L doesn't lose his children or cause a lot of drama for all of you in the community.
But you are poisoning your marriage by continuing to keep this a secret from him. With things like this, the earlier you come clean, the better. There is no benefit to be had from waiting it out, especially as every moment that passes leaves more chance for it to come out on its own and double your husband's hurt when he finds out that not only did you cheat, but you decided to lie to him about it for however long as well.