My girlfriend (F46) and I (M43) have an appointment with a therapist in a couple of weeks to discuss opening up our relationship. I'd like the community's help to prepare -- what books should I read, what subreddits should I peruse, what questions should I ponder to ensure that therapy is a success?

Note that she and I will not discuss this matter before the appointment, so I need to prepare solo.

Background

We have been together for 22 years. Sex was great the first couple of years, but then became less frequent (ten times per year, maybe), before dwindling to our current level (three or four times per year). I have stopped initiating. My libido is as high as it ever has been, while hers is obviously close to non-existent. I crave being wanted and desired.

We’ve been cohabitating since 2007 and have a child together. Aside from the sex, our relationship is great -- we're each other's best friends, work well together as parents and have built a harmonious home.

Back in 2018, she suggested that if her libido remained low, I should feel free to sleep with others. I wasn't interested back then -- I wanted to have sex with her and nobody else. The idea of looking for people to sleep with was off-putting and scary, as I'd had little experience with casual dating before meeting her.

She brought it up again about a year ago, and this time, I was frustrated enough for the idea to stick. I eventually asked if I could install Feeld and Tinder. She said, “Sure, let’s see what happens.”

During this time, I have made a concerted effort to be present in our relationship and make time for her. We have gone to lunch a lot more often than in the past and we have had lots of quality time (not much sex, though).

I have also tried to have conversations with her about non-monogamy to prepare her for what was to come, trying my best to put ethical non-monogamy into practice. I thought these conversations went well.

I was able to meet up with women, some of whom were only interested in being friends (which I'm very much open to; the majority of my close friends are female), while others were just looking for sex. That made me realize that I don't want to sleep with people I don't know or trust and that the only route for me is to form friendships before (potentially) proceeding to the sexual stage.

She did have issues with my meeting these women -- "sometimes I get the sense that you're going on actual dates!" She had this idea that I would meet up with women for quick and easy hookups.

I finally found an attractive, sexual, intelligent, married woman practicing polyamory. She was instantly attracted to me, and I to her. We chatted around the clock and had many phone and video conversations. After two weeks, we made plans to meet up in a city around two hours' drive from our homes.

She was very much attracted to the idea of having sex on our first date, while I was hesitant. She did prevail, and we wound up spending five wonderful hours exploring all the things we had talked about. I felt wonderfully validated and would never trade it for anything.

When I got back home and told my girlfriend what had happened, she was livid and threw a tantrum that very night (my son wasn't home, thankfully).

"You were naked with this woman? You had sex?", she asked me, incredulous.

I informed my married friend that it would be best if she and I did not have sex the next time we saw each other. She agreed.

We met up and had a pleasant day at a beach. When I was on my way home, my girlfriend sent angry texts, asking if I had enjoyed having sex with "that woman."

I truthfully answered that we had just hung out. That turned out to be even worse from my girlfriend's point of view, because at that moment, she realized that I was actually looking to form friendships with the women I saw, not just have sex with them.

The friendship part is non-negotiable to me. I need to have the same privileges I have always enjoyed with female, platonic friends, including being able to travel with them and spend the night.

Additionally, I very much want to fall in love. I have, in the past, with platonic female friends, without informing either my girlfriend or the person I fell in love with. I have enjoyed and benefited from these feelings. At one point, they lasted for two years and helped me be a supportive partner to my girlfriend while her sister was dying of cancer.

So I cannot accept having to choose between having sex with a person or being this person's friend -- then I'd actually choose the friendship. That means that what I'm looking for is polyamory, I think.

I should also mention that my girlfriend has had serious health issues the past five to ten years (though her low libido predates these health concerns). I have, during long stretches of time, been the sole caregiver to our son while my girlfriend has been battling her health issues. She believes that I have literally saved her life through my actions.

Couples' therapy

My relationship to the married women fell apart for reasons unrelated to my girlfriend. Her final piece of advice was to find a couples' therapist. Our first session is scheduled in only a few weeks.

I perused this subreddit last night and quickly had a number of "aha" moments, which to me is indicative of not having prepared enough. For instance, I was stunned to learn that there's a thing called "relationship hygiene."

So -- what should I do to prepare? Should I read the Ethical Slut, Opening Up or something else entirely? I'm not too big on podcasts and YouTubers, but I'll consider them too. I prefer something practical to a long academic treatise.

Thanks for reading this far. I'd greatly appreciate your advice and resources to make the most of therapy.