Am I too sensitive?

This is rubbish OP, it seems pretty damning to exclude you from last Christmas with the loss of your Mum and without you having a partner or your own family... Seems heartless to not have an open door policy under the circumstances. She seems cold and unreasonable to leave you out and to expect you to babysit and miss out on family occasions. She is taking the biscuit. Completely reasonable to step back and focus on who supports you, and adds to your happiness.

told me her and our Mom frequently met up without me because I have nothing in common with Moms

This is a dreadful thing to say on so many levels. She is not nice to you.

This, this, this. You need to emotionally detach. She doesn’t like you.

The fact that both of your parents are dead by your mid-20s (and possibly hers too?) makes her response even crueller, imo. It's very sad but I don't know that there's much you can do, except recognise the change and build your life elsewhere. Don't rely on her for emotional support or family togetherness.

You are absolutely not being too sensitive. She is gaslighting you by saying that to you. She's a dick and I'd back off from her. Sorry OP. Sending love x

Op sorry for your loss unfortunately people differ in grief they can push people away or rely on them more. Op your not being over sensitive your lonely you miss your mum and you had hoped that your ds would be there for you as you would be for her. With her having a family she will just carry on as she has too. Op your void has just become bigger because your ds isn’t being supportive she’s wrong to say your over sensitive your grieving everyone is sensitive when they lose family especially parents as they hold them family together. Are you getting counselling for your grief? You want your sister because you’re processing them the same grief but as a parent herself she really has to crack on. I wouldn’t push her away but I would try and fill your time away from her for now. She might be struggling emotionally and feels you are trying to lean on her and she’s got enough on her plate. Do you get on with her dh? Maybe she’s having his family more because of your loss there making memories because his parents will pass away eventually and they have realised life is too short. Don’t give up on her.

She’s behaving horribly to you, but this does sound out of character? If it’s only since your mum passed, do you think she finds you difficult to be around for some reason relating to that? Not to justify her actions, but maybe she’s not coping well at all with the loss of your mum and is pushing you away for some reason.

Don't accept this awful behaviour, sister or not. Why would she be angry because you cannot babysit? Why can you only come over to drop gifts off and not attend the events? I would be having an extremely brutal conversation with her and be prepared to not speak again. My mind does also go to the 'is she okay' is her husband not wanting you around, does she have some jealousy from childhood? That's the brutal conversation to be had

Looks to me like she just wants you to deliver presents and provide babysitting.
I would tell her that I feel excluded and you really only want benefits from me and do not feel you need to reciprocate.
I think you have handled this very well- being told you are too sensitive is just a way of shutting down your concerns. I suspect your sister is jealous of your child-free status- since she seems to bring it up so much.

Your sister sounds a bit like mine - pretty awful really. I’ve not fallen out with her but I keep a distance unless it’s birthday etc, then it’s a present. Try to concentrate on your other friends/family otherwise you’ll keep getting hurt.

She sounds like a right cow. 'Family focused celebration'? You ARE her family!

Were you actually close before your mother passed? Is it possible you are reaching for a deeper bond due to being younger and having less family, and she’s just not either interested or aware that’s what you want?

I'm sorry OP, she sounds very selfish and obviously doesn't value the relationship with you as a sibling. My sister is single and child free and has always been at all our family celebrations and holidays and our children are close to her. It's a shame that having lost both your parents, she isn't willing to include you in family celebrations. But you don't want to be where you're not wanted and loved. Concentrate on the people in your life who do love and appreciate you and stop making the effort with her.

Exactly this! She sounds awful.

She's nasty. You're not sensitive. Excluding you is bad enough, doing it so soon after you lost your mother is worse, actually using the reason for excluding you being that you don't have family is disgusting. To try and use you for babysitting and then get angry when you don't is awful. I'd not do any favours for her again.

She’s being a dick.

Where’s your Dad?

She sounds mean, my sisters and I would never treat each other like this. She may be jealous of your single and responsibility-free life therefore projecting. It also sounds as though she is competing with you for who was mum's 'favourite'.

Everything in your post was transactional. You don’t just have people in your life for their utility at that point in time - it’s a terrible way to view your relationships.

Ignore that poster OP, everything they have said is completely transactional and not the basis for a functional relationship.

Your sister is being very cruel, and in your shoes I would take a step back and do my own thing to be honest, you’re worth more than just being an unpaid babysitter or an afterthought.

To clarify, I don't use my child free friends, I was the child free friend and loved to help them. Even now I have my own child, I make time to see them without him so that I can help them. I think anyone with kids should be grateful when they have friends or siblings wanting to support them in that way. I don't think they should expect it though.

I also rarely see my sister as she doesn't live nearby but we live similar lives now we both have children so we talk more as a result. That's not transactional as we literally get nothing from eachother, we've never babysat for eachother or anything, just have more in common now.

She laughed saying I'm too sensitive

This alone is not behaviour to tolerate.

When someone says you're too sensitive its a form of verbal abuse and gaslighting designed to invalidate your feelings, deflect accountability, and make you doubt your perceptions. It is a manipulation tactic used to defend abusive behavior by shifting blame onto your reaction rather than the disrespect itself.

She isnt a nice person, she doesnt value you, or your relationship. This isnt a relationship you can save, because you cant control her actions. You can only control your reaction. You cant make her love you, you cant make her respect you, you cant make her value you. You can only decide if you are willing to tolerate her behaviour; and if you will continue to let her be around you to treat you how she does.

It's not you.