You have had a big shock this week, of course you are all over the place. That is perfectly OK and normal. Anyone in your situation, regardless of their own past experiences could find themselves trying to make sense of a horrible situation by putting themselves as close to it as possible.

I recently found myself doing exactly what you have written about. I'd been safe for years and suddenly I was coming up with an ideal plan. That really scared me, I was terrified that I was going to lose all those years of strength and that once I lost my safety it would be gone for good. I got as far as choosing and visiting the place and I was about to collect what I needed and then suddenly I realised "what the hell am I doing?" In all that time I hadn't given a thought to the people I love, that's when my safety net suddenly caught me and I was back to feeling almost safe again, but I was shocked and mortified by how far I'd let myself slip.

You need to remember that you control the thoughts, they don't control you. Importantly, even if it doesn't feel like that to you, by writing about it you are taking control. It sounds like you have a safety net, other posts of yours suggest you care for the people around you and don't want to hurt them.

I developed a mantra to help me back to a safer place, maybe a mantra would help you too.

Mine was

Thoughts are just thoughts* they don't have to become plans*
Plans can be changed* and don't have to become actions*
Actions can be broken into stages*, you can stop at any time* actions are not inevitable*

The stars* are all times you can ask for help and remember it is never too soon or too late to ask for help.

If you don't want to bother your crisis team (I can understand that) and you don't want to freak anyone out, have you thought about talking to the Samaritans? They are really good because they don't send anyone round to your house and if you hang up on them it doesn't matter. They are really good at just listening, no judgements and no risk of ending up on a ward when you really don't need it.

Stay safe and strong, and believe in yourself, you've got this far because you are a strong person.