Flowers for another woman... What is he thinking?

I am having an issue with my husband... like a serious one! I read a text in his phone from a girl who works at one of the clubs that he frequents on the weekends... She said "loved the roses you gave me last night... wish you would have given me a good night kiss before you left!" The text was from Sunday morning at like 3:45 a.m. which means she was talking about Valentine's Day!! What in the heck? He gave someone flowers on Valentine's Day and didn't even come up to see me at work that night! He says that he found the roses outside of a different club and had a bet with one of his friends that whoever gave them to the fattest girl didn't have to pay the tab but I don't think I am buying that excuse... What would you do in this situation?