Dreaming that your spouse is cheating on you, and you're experiencing jealousy, indicates your fear of being abandoned. You may be feeling some lack of attention in your relationship. Or, you may feel that you are not measuring up to the expectations of your husband. If your husband is not giving you any reason to suspect he's having an affair, or that he will leave you, then you must look to your 'self' for the reason behind this type of dream.

Do you feel inadequate in any way?
Do you feel guilty about things you say, or do?
Do you feel as though your husband is showing you less attention?
Is sex becoming less frequent?
Have you felt like the 'romance' has been lost from your relationship?
Do you feel as though you could be 'nagging' him about things?(Or were you accused of it?)
Are you 'getting older' and possibly feeling a bit of a 'mid-life crisis' happening?
Have you gained weight, and may be feeling un-sexy, or unattractive?
Because the dream is recurring, is it happening on or about the time of your menstrual cycle?

I hope this helps you out, good luck!