Stay with your husband!

The friend you're talking about is negative and cruel. Enough said. If your husband has the more posotive attitude, then it will be more likely to work out in the long run. You're just feeling like the grass in greener, but trust me IT ISN'T!
Tell your husband that you aren't completely satisfied with your relationship as it is, and that you would like to connect with him on a deeper level. Seek marriage counseling. Work hard to get to know the deeper parts of each other. Women need to feel deeply connected, in order to feel loved. Men need to feel respected, in order to act loving towards their wives. Be respectful!
I left my husband for a friend of mine. It was great for about 10 months, then reality reared its ugly head. It isn't worth it! Don't do it!
Break off all contact with this friend. By the way, a true friend would never even suggest that you leave your husband or cheat. A true friend would have your best interests at heart, and would stay away from you out of respect for your situation. If he is hinting that you should get together, or that you'd be happier with him, then he is selfish.