stuck on my ex?! help

Me and my ex have known each other since we were about 10 years old and always been family friends. We are now 23. We ended up getting together just over 3 years ago and it was like having my best friend and my boyfriend in one, it was perfect. We ended up having our son after a year of being together as well as moving in together (everything came at once and it did put pressure on our relationship). Over Christmas he walked out on us and said he needed space. When our son was 11 months old (the January) we decided it was best if he moved back to his parents and we called it a day as the arguments were near enough every weekend and it wasn’t healthy.

In the end of March of the same year we both seemed to want to see how things went between us again and we started going out as a family for food and days trips out. We spent Mother’s Day together and his birthday also. During this we did still bicker but over silly things that would be forgotten in a few hours. We eventually got to the point where he was staying every weekend and we both had said things were going really well. One Monday at the start of June he told me he was ready to come back home and I agreed. The following weekend he was very off and didn’t want to stop over like usual even though he stated he was ready to move back in. Feeling confused I left him to it and waited a couple weeks to go by. He ended up staying another weekend but he said maybe we should hold off him moving back. I let this go and the following weekend he was very cold and didn’t want to sleep over but we did still go out for the day shopping as a family. When we got back I asked to know where I stood and he told me he didn’t want to be with me and he had been forcing himself to be with me for the sake of our son. I asked if there was someone else or something else going on as we had both said we’d been happy and he had even wanted to move back. He promised there was no one else. The following week I found out he had ordered sex toys off the internet worth over 50 pounds and confronted him, he admitted he had been messaging a woman from work and had decided to see where things would go with her now he was single.

He promised it had been nothing while he was still seeing me but I find it hard to believe he’d have ordered sex toys for them if they hadn’t been intimate before. I spoke to someone I knew from his work and they told me that at their Christmas do she had tried to pursue him and there had been rumours from December that my ex and this woman had a thing and the lads were always throwing jokes around about it. Which maybe it would make sense him walking out over Christmas due to guilt? I’m just very hurt and very confused and trying my best to get over it all but it’s not as if I even had a sign he didn’t want to be with me, he had even asked to move back in. So my mind is all over the place. The person who works with them both has told me she’s always had a thing for my ex and she has tried to pursue him a lot.

I thought maybe he had left as he was struggling to commit to being a dad and in a long term relationship due to being quite young but the woman he is now seeing is 10 years older than him and still married (not living with her husband) and she also has a 5 year old daughter. Without sounding like everything is about looks, he’s also always been quite shallow in the fact he has a typical type, curvy and blonde, he even asked me not to lose too much weight on a diet so I didn’t lose my curves. This woman is the opposite of curvy without sounding mean and she’s also nothing like his usual type. So I’m very confused as to where his head is and it hurts to know I don’t even know who he is anymore, everything about him has changed and he’s going against everything he has ever said.

I also said I’d leave them to it as long as she didn’t have anything to do with our son for a good period of time and I then found out she had met our son as she turned up at his house while my son was there and he let her in and let her meet our son. This left me feeling very hurt as I’d already lost his trust with me but always thought he’d have his head screwed on when it came to our son. I’ve said if he proves that they’re getting serious by all means our son can see her again but if he’s telling the truth and he’s only been properly seeing her for a couple weeks then that should never of happened.

I’m trying to think positive and tell myself one day I will find someone that treats me how I deserve to be treated but I’m finding it really hard to believe he’s as happy as he’s making out and that all of this is a way of him pushing everyone he loves away as he’s also cut off a lot of his close friends. It’s hard to see him in such a different light as it’s not the person I know and love.

Sorry for the very very long post. Just feeling very lonely and needing advice or some words of encouragement.

Thanks in advance xxxx