I answered you post in home invasion. I guess this is a post that is going to take a bit longer to answer. There will be many here who have suffered in the same way and will be able to understand what you are going though.
I've had anxiety, together with PTSD and bouts of depression for a very long time. I have not found one single thing that stops that type of thinking in its tracks. What I have found is that approaching the problem from several directions can be quite effective.
Firstly I am under ongoing regular therapy, originally ordered by a GP but now with a psychiatrist. I take meds and have a number of strategies to minimize both background every day stress and coping mechanisms for anxiety 'attacks' as they happen.
I try to avoid anything that I know can ramp up my anxiety levels, such as certain types of conversations, certain activities and in particular get to know my triggers - and avoid them where possible. Some stress in life is inevitable of course. Exercise and healthy eating combined with sleep hygiene all help. Also distraction - I tend to loose myself in books, and to a lesser extent in movies.
When I'm in the middle of a anxiety 'attack' (panic attacks are different for me) with my thoughts whirling and 'catastrophic' consequences in my mind I try to do some sort of physical activity, go into a different environment, and use an app called Smiling Mind. I might also have a conversation with my partner if she is available.
You sound like a whole host of trigger factors are taking place at the moment, parents away, daughter going away, a new job.
Frankly I did not find I was able to soldier on by myself, I really needed both medical and family support. I know you said you had 'top-ups' of counseling. I'm wondering if that is actually enough - it does not sound as if it is effective at the moment.
If you are not under regular care may I suggest you book a long appointment with your GP and set out your history, current state and what is happening in your life at the moment. I found I had to write it all out first, then share the paper, in order to give a clear picture
This may result in meds, a Health Plan, a psychologist and therapy - something you can work on together
You might benefit from a browse of the Forum to see how others have coped in similar situations. You could start here
I hope you post again