I really don't know which direction to go
Let me give some context before.
On the end of my marriage (around 2015), my ex wife imposed to me, for us to open our relationship.
She basically came with the speech that she wanted to date other people and that if I didn't accept that, it would be because I was a chauvinist that didn't respect her decisions over her body.
So, I ended up accepting it, and started dating other people too. Of course this meant the end of our marriage, but this was inevitable even if we didn't open the relationship.
After that, I started to deepen my relationships (strict friendly and corporal) with mostly non-monogamous people.
And at some point I met my girlfriend. She freaked out about even considering having something non-monogamous. At that moment I was so in love, that I didn't care about being with other people or not. But now, after several years, and many many love deceptions in this relationship, I noticed that I am starting to feel attracted to other people.
I didn't do anything, but I noticed that the desire is growing.
I still love my girlfriend, and I'm very confused about even thinking about being with someone else. But I know if I would, at some moment, my love for my girlfriend wouldn't change at all.
I'm very confused. I don't know what to think or what to do. I'm scared of losing my girlfriend, and at the same time, feel more and more attracted to others.
What advice would you give me?
I am 100% sure that I can't bring this topic to my girlfriend, or it will inevitably mean the immediate end of our relationship. So I have to figure it all out by myself. At this moment I have no idea which direction I really want (or can) go.