Suddenly jealous of a woman he dated

[Jordana4194w]

This is a difficult one and I’m prepared to be told I’m unreasonable and to move on but I have an issue that still upsets me occasionally.
I have been with my boyfriend for 4 months after getting to know each other and going on dates for 9 months prior. He was also dating other women before we were serious, so the first 3 months of meeting. I knew and understood that he didn’t need to be loyal to me initially as we were in the early stages of talking. Obviously I didn’t know the extent as I respected their privacy and didn’t ask. He chose me after feeling we had better chemistry and got on really well, he didn’t divulge much on the other 2 women just that it fizzled out after a few dates.
I came across photos and Facebook posts from one of the women about a month into our relationship, (on a group related to my hobby after I had a nose as I recognised her name from somewhere-he met her on the same Facebook dating group) nothing worrying, just from the time they were dating talking about how much fun she had with him and hopes he’s the one. It got to me more than I expected. He visibly took her on nice expensive dates (not a priority to me) but it felt like a smack in the face how happy they looked together. Our dates at the time were free and local (had a lovely time) so it made me question if he even chose me because he wanted me to have made less effort and plans for our dates. I don’t believe he was turned down and wanted to be with me as I was the last option, which I’m sure many of you will think, I do believe it fizzled out as it can if you realise you’re not a match.
Everyone has a past, and he’s accepted my ex husband and child as my past, but I find it upsetting to know he had other options alongside me to begin with and that he may have made more effort with the others.
I have spoken to him about how I feel as I admitted I saw the posts, he apologised and reassured me it’s in the past etc and he’s glad he is with me.
I guess I’m just being insecure as she seems fun and more his type than me so I worry one day he might wish he’d chosen her instead. Any one around to shake some sense into me as I feel jealous of a woman I don’t know just because she had 3 lovely dates with my now boyfriend.

Maybe she arranged the dates?

This way madness lies. BELIEVE ME - I've been in this situation and ended up in therapy.

Honestly, it's in the past and it's irrelevant. Don't let it jeopardise what you have. You can't possibly know one way or another what actually happened between them so done torture yourself. What you do know is that you're happy now and he is your boyfriend, not hers.

More likely he turned her down because after just a few dates she was posting shit on his Facebook like 'I hope you're the one'.

Tbh op, it doesn't matter why he picked you. So long as he did. And as long as he is treating you right. It would be different if he was bringing these people into the conversation or doing other things that made you feel insecure in the relationship. But this is just you being a silly beggar. Put down the phone.

Thank you all it’s nice to hear from other perspectives, I know it’s a crazy way to behave it’s just strange that he could be with her and not me, maybe I’m still holding onto some jealousy he was dating us at the same time and didn’t instantly know he preferred me from our chats and chemistry? Yes such a teenager way of viewing it but I am fairly insecure in general

I don't like the sound of this multi dating, why can't people just decide if they like and decide on the one person there're dating or not, I'm not surprised you feel a bit jealous if she got treated better then you at the same time.

If he was dating her for 3 months and others while just getting started on talking to you, he must of been intimate with her, I'd be pissed off if was her, maybe she realised and dumped him, just because you don't have the talk, he basically gets away with this behaviour.