To not want him to go?

[PollyPock]

My partner of 5 1/2 years used to run with a male and female friend on a Sunday morning. The male friend stopped going as much and so he would go with the female just the two of them. Female is married with a child. She then got pregnant again and stopped running and it fizzled out.

partner has recently done a race and wants to get back into running which I’m supportive of, he is now starting to run with the female again.

I have no reason to think that he would have an affair but I hate the fact that he’s out running with another woman while I’m in work/looking after our child. It seems so silly and petty but I just feel like this is how things start and they do seem so innocent at the time.

he is a fab partner mainly, not a flirty guy or anything like that. I’ve never met the female.

You are, in a word, being ridiculous.

I think it's perhaps slightly normally to not want him to go - but personally I would think it was a bit controlling if you actually stopped him going.

She's a married woman with two children, your partner is with you - I hardly think that running (which I prefer doing with people too!) is going to be the start of an affair. You just need to reframe your thinking about it, and make sure you get some time to yourself too.

How ridiculous

It isn't reasonable to ask your partner to give up his female friend or hobby because you are feeling insecure, especially when he has never given you any reason to doubt him.

You sound jealous OP. Lack of trust in a relationship is a real slippery slope. Not a pleasant trait.

You either trust him or you don't 🤷🏼‍♀️

It's understandable, but unreasonable.

You're being entirely unreasonable, right on down to your repeated use of "the female."