AIBU to be upset about silence and no explanation?

She didn't accept the coffee and chat offer because a plan to do something wasn't what she needed. She wanted an expression of care not an offer.

You're neighbours and friends - did you text to ask how she was? Drop in a card or flowers? ask about specific stuff to initiate a text conversation? Offer to pick something up from the shops? Or bring back a borrowed item and have a doorstep chat?

Regretfully, asking the favour a second time and then panicking and pressing it is what's tipped her over the edge.

If she was bereaved in autumn and you initially asked around Christmas then I think that was far too close to her loss to have asked in the first place, though she seems to have declined graciously then, and Christmas can be a very challenging time for grief and loss. To then have asked again sometime within the 2 months since Christmas (possibly less depending on when exactly you asked for the second time?) does seem like another instance of insensitivity on your part unfortunately within a matter of weeks potentially...

I don't think you have really done anything wrong. It's difficult for all of us to understand how someone else is processing grief. I saw a friend today who was widowed last autumn and she is struggling just now - to her surprise because felt things were getting easier. It's not a linear progression.

You’re absolutely not an idiot @Lifeinblackandwhite . Please don’t blame yourself. You reached out because you’re a kind person. Just let this go if you can. Your friend is processing grief, it’s horrible and heartbreaking for her. I’ve been there, two months for others is like two days for her. Get something else sorted for your cats. Your friend will find you when she’s ready. Possibly months down the line. Let her grieve at her own pace. You’re a good person to care so much x

I really wouldn't leap to thinking your friendship is over. She may just need a pause. She might feel guilty about not being able ti help with your cat, and be stressing over the fact she has your spare key and therefore no one else could use it.
I would just leave it for now and maybe send her a card/flowers in a month or two saying you hope shes OK and would she like to go for a walk.
It doesnt sound like you have done anything wrong at all.

Don't write it off, @Lifeinblackandwhite -- chances are this isn't some kind of permanent estrangement, so don't be too said. I think you'll be doing the best you can to give the friendship a chance to come back as strong as ever once your neighbour is feeling better by posting your key through her door with a nice card saying you were sorry if you were insensitive in asking her to look after your cat again, you appreciate she needs time to recover, that you're thinking of her, and would happy to hear from her if things change in future.

Just smile and say hello if you see her.

I got a friend back after nearly a decade of estrangement in the last few years.

I agree @SillyQuail

I think the silence is a bit cruel to be honest.
Nobody's perfect, it's not like OP has done anything horrible.

I don't really think you've done anything wrong, you were kind and supportive and even if that wasn't what she needed, she must know it comes from a good place. I think eventually she'll probably start talking to you again if you back off now, and when she's feeling better she might explain her behaviour. At the end of the day, if she doesn't then really it's her loss since you actually care about her and want to support her. I wish you were my neighbour!

It's probably more to do with her grief, rather than anything you've done.

It sounds like you've been caring and supportive. I suppose she might be annoyed you've asked about the cat but the silence and giving back the key without explanation seems harsh. She's left you wondering what's happened, which is horrible for you.
I would send a card to say sorry if you've upset her? and you wish her well. Then leave it. That's all you can do really. But I don't think you've done anything really wrong.

I’m sorry OP. Being ND it can be very hard to understand social norms. Don’t be too hard on yourself. This friendship may be rekindled in the future. For now, concentrate on your other friendships. It’s very hard to get things right when you don’t understand th ‘rules’. I hear you.

I think you asked, she said no she wasn't in the right head space, then you sent her other messages which she ignored. That was the point to recognise she wasn't in the right space to communicate, give her some space maybe even brave and say I'm still here for you but I don't want to push you so I'm going to back of, please get in touch any time, not ask again if she could mind your cat. It comes across as pushy and insensitive

I’d say her giving your key back is her signalling she’s not able to help you right now - you might need to give the key to someone else. Honestly if she’s in deep grief, this will have very little to do with your actions- she just doesn’t have the bandwidth to explain herself to you properly right now. Don’t take it personally & keep up the kindness towards her.

When my dad died it was several months before my mum was even vaguely approaching back to normal.

she probably did not feel ready to start doing stuff again and given she said no at Christmas and didn’t respond to your first message you should have left it.

it will have been the additional two messages chasing that did it.

for what it’s worth, while people do occasionally forget to reply if someone is not replying it is often deliberate and a clue that they are not happy with the interaction,

But you have upset her, by asking her again to look after your cat shortly after she'd told you she wasn't feeling up to it. When you're grieving or feeling fragile or extremely low, all communication can feel like a demand, and I imagine your second cat minding request felt as if you were badgering her.

I'd do what @bridgetreilly suggested, put it out of your head for now, find someone else to mind your cat, and spend time with other friends.

Yeah, the returning of the key with no communication as to why seems a little harsh, but when people are grieving, their emotions can cause them to make blunt/rash decisions.

If you’ve caught her on a particularly bad day emotionally with your follow up message, then it could’ve just landed in the wrong way and she’s just lashed out.

Give her space and a bit of time.

As someone else said, you could always pop a note through her door just saying you’re sorry if you’ve upset her in anyway, that would never be your intention and that you’re still there if she needs to talk. And then leave her be and let her come to you if and when she’s ready.

You’ve been a bit pushy tbh OP and not respected her grieving. I had a pushy ‘friend ‘ who acted so personally affronted when I pulled back from communicating much with friends after loosing both my parents. I never spoke to her again after that.

they’d done something to really upset me

I think you have upset her by asking again so soon

Ah she told you firmly she wasnt up to it and you asked again a short time later

I think she feels that you dont understand her depth of grief and are pushing it.

Its a bit blunt to ask again almost straight away not even having met up tbh