Is AUTHOR wrong in the post ? POST : So I (30M) and my ex (30F) who dated for five years have been broken up on and off the past two years and officially done for eight months. We moved to a city together when we first started dating and have a lot of the same friends. 

The reason I bring this up is that a few years back we tried to open up our relationship and one weekend during that time while my ex was out of town, I ended up hanging out with one of the women (35F) in our friend group for an entire weekend while my ex was gone. Nothing sexual happened but I did spend the entire weekend at her house. Things didn't go over well with my ex (I told her immediately when she got home) and at the time caused some turmoil in our relationship which we were able to overcome.

There was also tension between my ex and this woman, but quickly the two of them became closer than they ever had been before. It should be noted that my ex had hooked up with a random guy while I was out of town previous to this while she was out with a few friends so most everyone knew about this open relationship thing.

Fast forward to about a year ago and I was out with some friends and ran into the same woman. We hung out and I spent the night and the following night at her place (nothing sexual happened again) and that was that. We both get along well but she told me she cared about my ex and didn't want to hurt the relationship since they are closer and better friends now. I was respectful of this and that was that between us other than seeing each other at various get-togethers.

Fast forward to about a month ago and we find ourselves together at a bar and hit it off quite well as we do except this time she texts me after she leaves. Since that night we have been hanging out together (No sex still at this point) and things are going well. She has mentioned that she really likes hanging out with me but still has the same apprehension. I understand where she is coming from and this is the reason why we haven't had sex or started exploring this relationship more. I really want to be respectful but I am kind of letting things happen and not fully supporting letting this thing go since I like this person.

I don't want to compromise my ex and this womans relationship but part of me feels like my ex is somehow controlling this in some capacity. The reason I say this is the first time after we spent that weekend together I was getting the vibe that my ex put herself more in this womans life to check that nothing was going on between us and is still doing that. I don't view my ex in a bad light and I still love her very much as a person and I know she feels the same about me but my ex wanted our relationship to end. I feel like I would have some sort of regret if I just let this all go and didn't pursue this to some degree. I have tried to look at things as if I was in their shoes and I just want what is best for everyone. AITA for not just letting this whole thing go and only seeing things from my point of view?