Dan Savage originally answered this question at Savage Love on October 21, 2010, and he did a piss poor job of it. His answer was fraught with victim-blaming, shaming and unnecessary judgment. I have a policy of not linking to his site, but you can do an archive search at Savage Love if you really want to see the original.
Question: My husband and I have had an open marriage for the last two years. Up until five months ago, it was working beautifully. At that point, however, I was sexually assaulted by a former partner. Since that incident, I cannot stand sex with my husband. I completely flip out when he tries to initiate sexual contact. My skin crawls. I become panicked and feel repulsed. I just cannot handle it. Those times when I go along with it anyway leave me feeling enraged and disgusted.
I don’t think this is completely unheard of for someone who was relatively recently assaulted, and I am considering therapy to help me work through it. The immediate “problem” is that I have no difficulty having sex with my boyfriend. In fact, the sex with him is amazing and leaves me feeling loved and whole and wonderful.
This is breaking my husband’s heart. He has become incredibly jealous of my relationship with my boyfriend. He’s depressed. He’s angry. He accuses me of no longer loving him, and he wants me to stop sleeping with my boyfriend until our marriage is back to normal. I feel like a horrible person, but I just can’t do that. I need that outlet. I need that support. And I admit I have a hard time 
believing that my husband and I will ever be able to go back to the way things were before.
I feel like I’ve already lost my former partner (fucked-up though that may seem) and my husband. It kills me to think about cutting out the one positive relationship remaining. On the other hand, I do love my husband—very much—and watching him suffer like this is unbearable.
Potentially Traumatized Sexual Deviant
Dear PTSD,
Wow, I am so sorry. This all sounds so difficult, and it’s great that you are asking for help.
First things first, I strongly encourage you to seek out a trained sexual assault counselor to help you start the journey to healing. Most sexual assault service agencies provide counseling that is based on an empowerment model, and best of all: it’s usually free for survivors. You can find out what agency serves your community through RAINN at 1-800-656-HOPE. I’m not 100% in support of all of the things RAINN does, but they can connect you, immediately, to the local sexual assault service agency. Even if you don’t have time to sit down with a counselor, you can use the crisis and support hotline.
For the affiliated troubles, it sounds like you have some hard decisions to make about your relationships with both your husband and your boyfriend. It also doesn’t sound like your husband is being very supportive (and perhaps your boyfriend is), and maybe he is feeling wounded because his wife was sexually assaulted. I have no patience for that. It didn’t happen to him.
It’s reasonable that he would have feelings like sadness or anger about the sexual assault, but it’s not reasonable for him to hold you responsible for those feelings, as if you did something to him. What does he hope to get if you stop the sexual relationship with your boyfriend? Does he think it’s a magic fix? If you are feeling repulsed by the idea of having sex with your husband, that doesn’t have anything to do with your boyfriend. It has more to do with your husband, and his reaction to your ex sexually assaulting you.
There are places he can seek support as the SO of a sexual assault survivor, FYI.
CARDINAL RULE: You don’t owe your husband sex, but you should probably be honest and direct. If you are feeling unsupported, say so. Let him know what might be supportive. If you are committed to staying married to him, being honest about how his demands make you feel might just be a good start to a new chapter in your lives. Maybe there is room for compromise on your sexual relationship with your boyfriend, If he’s not willing to hear it, then it may be time for some marriage-related navel-gazing for both of you.
Good luck, and again, I am so sorry that this happened to you. Keep me posted.
Cristy
Cardinal Rules 
So much yes!
Yeah! And your address starts with a 2— easy to jump over here. Savage is a vampire. It’s still amazingly difficult for a lot of women to put their needs first in their relationships with men. It’s risky, but successfully doing it is getting a whole new lease on life and taking good care of ourselves. Men do it unconsciously and it can be a chore to get it across that some reciprocity is in order. My philosophy for relationships from marriages and couplings of all sorts to a traditional family is “everyone’s needs before anyone’s desires.” When respected and practiced, it’s just a matter of sorting out whether something is a need or a desire, and the case of recovering from a rape, the distinction is unquestionable.
As a survivor of rape, and as someone who lived through sexual assault (from a third party) after I met my current partner…
Right on.
I have zero patience for anyone who prioritises their own feelings over those of the victim, or who does anything *but* listen patiently as the citim works through their complex feelings. Making demands of someone who’s recently traumatised, or who has recently come to terms with trauma, is unacceptable. Period.