This might be an indication that you are looking for someone else and there are problems with your commitment to the marriage. If you are confused, I suggest you find a therapist to help you examine your feelings about your marriage and your flirting. By all means, take this very seriously. I commend you for asking the question and beginning to take a look at yourself. Don't fool yourself.
Internet relationships can quickly get out of hand.
It is impossible to compare a long-term marriage with an Internet relationship. I recommend you make some decisions about the marriage before you start looking for alternatives. Try to fix the marriage first and seeing a therapist is a good start. There is not the personal investment in these relationships. There is less need for lying, extortion and fantasy.