Not sure if I'm being unreasonable here and a bit precious and should just let it go or if I'm justified in being rankled a bit.
My DP and I don't live together yet (we are planning to at some point when he can sell his house) and each have one DC, similar ages (pre teen). Kids get on well, I get on well with DP's child and vice versa him with mine.
So as to not drip feed, DP goes back to his parents at weekends when he has his DC as due to DP's exW having the house which he still pays 50% under the divorce he cannot afford anywhere suitable enough to live to have his DC over at weekends.
DP and exW are amicable and she's a pleasant person, we are civil, shes just not my cup of tea. We've messaged a few times about their DC so communication is open but I've only met her a few times in person when on the odd occasion I've been with DP when we've picked up DP's DC. All fine and friendly.
Once a month or so, DP and his DC come to mine for the whole weekend. Food costs, going out etc are split between my DP and I on these weekends. I wouldn't expect his exW to contribute as he has DC every weekend. However I never even get a thank you from DP's exW for having her over at my house. For the record, I don't get involved in parenting his DC as only known DC for a few years, I treat his DC more like a close niece/ nephew so it's not like his DC is expected to stay at my house as part of contact arrangements.
I do it as I love having his DC here as we have a great time all together.
AIBU to expect DP's exW to just say 'thanks for having her over at yours' in the same way I would do if my DC stayed at a friends house (including my parents who I always thank on the occasions they have my DC)?
She never has done so and I just feel there's no gratitude at all and it just grates a bit.
Not going to mention it to DP as dont want to appear petty and create issues where its only a little insignificant thing. But I just find it SO rude and it bugs me. Am i just being petty?