DH and I have been married nearly 10 years, we have a DD (6 yo) and DS (4yr old). DH has a daughter from previous marriage, she's nearly 20. Over the years I've really struggled. She's been very indulged by everyone (DH, her mum and grandparents) and literally never had to do anything for herself. I've tried to be diplomatic over the years and made suggestions which fell on deaf ears, at one point MIL told me I was out of order for expecting SD to help around the house (at the time DS was 16 and I'd asked her to help with the hoovering a couple of times - she had to be supervised as she couldnt do it). I have suggested there may something she needs help with, may have autism which she may need support with. Fast forward, she's nearly 20 and can't function as a nearly 20 year old. There are a number of issues which aren't her fault, as I say she's been over indulged over the years and I suspect she may have autism. She sits on her bed all day every day. She has applied unsuccessfully for a couple of jobs . I've offered to help which she's refused and I've made suggestions of what to do to make her cv better ie volunteering etc. My issue is, she is totally self absorbed doesn't care about anyone unless they are of use and sits on her bed all day every day. DS had massive surgery recently, when home from hospital she didn't even come out of her room to say hello. He was desperate to see her, it was really upsetting.
I'm struggling to tolerate the lack of effort with anything and feel like I'm about to explode. She lives with us 50% of the time and i cant bear it anymore. I dont want to be mean, AIBU? Does anyone have any suggestions or show me another perspective I may be missing?