Wow. Your poor daughter. She had to be really brave to tell you that your husband is PUTTING HIS HAND ON HER BREAST! AGAINST HER WILL.
And you sort of believe her and sort of don't. So you have a sort of conversation with your husband, where you treat this like a hug gone wrong, as opposed to abuse, where you seem to mildly say, "Hey, hon, love you, but my daughter would like to not be touched, okay?" And he sort of agrees and then goes back to doing it. And you just ignore it.
Can you please, please, PLEASE treat this as an emergency? Your husband is touching YOUR DAUGHTER against her will. And you can't even get him to agree to knock it off.
So treat this as being really, really bad. Take your daughter's side. Have a fit with your husband. Really believe your daughter and have a screaming fit at your husband. Let him know that THIS IS NOT OKAY! He is to keep his friggin' hands off your daughter's body, NOW and FOREVER. He is NEVER to touch her again, not under any circumstances, not for any reason.
Where's your MAMA BEAR in this? This is YOUR DAUGHTER. It does not make it okay because she's 19. She should expect that her mother's home is a safe place where she can come and feel safe. She should not have to deal with her stepfather groping her breasts and her mother being a wimp about it.
So tell him to KNOCK IT OFF. This is ASSAULT AND BATTERY. It is a CRIME!
I think you choose not to believe it because you want to have your little fantasy that your husband is a nice guy, and nice guys don't do this, so somehow your daughter magically isn't getting felt up by your husband. Come on woman! Deal with it! Protect your daughter.
Oh, and yeah, people make mistakes, but they also make amends. Your husband needs to apologize, and he needs to promise you and your daughter that he won't do it again. Then he needs to go to counseling with you, and he needs to ADMIT it, so you're all clear on it. And you need to go to counseling with your daughter, so she can tell you the real truth about what's going on, because I'll bet you don't know the half of it.
And you believe in second chances. Well, do you believe in third and fourth and fifth chances? Because you already told him to stop and he didn't. How many chances does he get? A dozen? A hundred? When does it just become that you give him permission to touch her because you don't make any consequences for him doing it?
BTW, I'm betting he's done this to other girls. I'll bet he has a reputation among her friends as the creepy stepdad who brushes up against them. I bet that none of her friends comes over more than once. And did you ever think that maybe he chose you when she was a young teen so that he could have some eye candy? Maybe he was grooming her even back then, because he likes them young, and was just waiting for her to turn 18. Ever think of that?
When you grow old alone because your husband has left you for a younger woman and your daughter won't bring over your grandkids because you didn't protect her, I hope you take all that alone time and think about why you preferred to believe a man over your child.
And news alert: these guys NEVER believe they're hurting anyone. There's a book called "What Cops Know" and they say that when they sit down with a pervert, the guy always describes a tender, loving relationship, and the kid talks about putting on four pairs of pajamas so daddy won't touch them. Face it honey, he's fooling himself as well as you, that's why he is so believable. And of course he doesn't intend to hurt her. He intends to get off on the ***** he enjoys by feeling her breasts against her will. He enjoys both parts of that, feeling her young breasts and the fact that she doesn't want it. And maybe he also enjoys that he has enough power over you emotionally or financially that you're just turning a blind eye to this and sacrificing your daughter so you can pretend you have a nice happy family.
When you asked her, she said it started "just a few weeks ago" but you open by saying she told you this months ago. So now it's been going on for months, and you haven't gotten him to stop. How many "second chances" does he get? Months' worth? Or do you just not mention it so you can pretend that he would stop if you gave him a "second chance"?
Frankly, you need to NEVER let your husband be alone with your daughter again.
And BTW, you are wrong about having "major husband daughter problems." You have MAJOR HUSBAND problems. Your daughter is just a victim. Your husband is the one who's giving you major problems.
I keep coming back to this letter because it's so shocking, the way you minimize what happened. You say you believe her, but you also describe things as "according to her" "allegedly" "not comfortable with affection" "not used to any type of affection" and "he could have done a lot worse." This isn't "affection." It is criminal to touch someone who does not wish to be touched, and it's sexual in that he touched her breast, and it's just horrible the way you seem to think that it's your daughter's problem and you wish you could all be just one happy family.
You also seem to say that this happened months ago, but your daughter still cries about it. Is it still happening? I think it is. I think she cries, not to make you feel guilty about it, but because she's stuck with this man and you don't defend her or help her, you just minimize it as "affection."
But really, your poor daughter. Her own mother would rather protect a man than protect her child.