@Mumtotwoxo I'm sorry to hear you are going through this! I haven't read all the replies but wanted to share my experience. I have also had intrusive thoughts that are extremely upsetting. I have a history of anxiety and panic attacks too. I remember I had been in a fairly anxious state and then bam.. one day, I had a horrible thought and I literally felt the colour drain out of my face, I was horrified!! I then kept questioning why I had thought that, and trying to think of reasons why it wasn't true. Does this sound familiar?
The horrible thought continued to repeat and it was as though it was hitting a giant red button in my brain every time, filling me with dread and fear and sadness. And again more questioning, reasoning and googling.. going round and round in an endless cycle.
Basically your poor tired anxious brain has made a horrible little pathway, it has taken a nasty thought which is very likely to be the exact opposite of what you want. It causes such distress and this in turn creates a cycle of distress and then trying to reason with the thought, trying not to have the thought (which doesn't work) and on and on. I'm sure there is also a rational part of your brain which cannot understand all this and on some level KNOWS that these thoughts are not you.
It won't be an immediate fix for these thoughts, what worked for me was deciding to have an absolute blind faith that these were JUST thoughts, and forcing myself to do all my daily activities and especially those that trigger the thoughts (this was very hard at first), continually until they gradually lost their power over me. I also did a lot of walking and running, even when I felt like crap and just wanted to hide away in bed! I think this helps to burn off all the crazy adrenaline caused by these thoughts and helps to break the cycle. Also a book called Anxiety No More by Paul David was really really good, you can get it on the Kindle app. You WILL get better, these thoughts always choose to attack the very things you care about most in the world and things that you don't want to happen.