Forgave but can't forget!!

To make this short. My hubby and I have been married for 1 year in which we've been threw our share of ups and downs. In October I found out that he had been "talking" to his female coworker about our problems and asking her for advice. When I spoke to this girl and I asked if she had slept with my husband due to other info he admitted to her response was why don't you ask him! Of course I took that as a yes and I lost it and I kicked my husband out. After a couple of days we talked about it and he swears up and down that all he did was confide in her and get advice. But when all that happened he admitted into having feelings for this girl then later he said he was just confused. I forgave him and let him back home but every so often I remember and I just cry and feel so unhappy!! What should I do??