First of all, welcome to the forum blueeyes :)
How do I know if the new thoughts are actually more likely?
The funny thing is that is more or less an inquisitive question that arises from unaddressed anxiety. The best thing to do is to see rationalisation as a natural process, not something that is linear. That is, new thoughts and new behaviours are formed naturally and it's about exploring them as they come along. Thus, it's takes an attitude of curiosity to see cognitive change as organic.
I have decided to try the cbt again, but am now worrying that the rational thoughts my psychologist and I have come up with are not actually rational at all and that the likelihood of having to give up my job is high. I can't see myself trusting my thoughts enough to try for another baby again and I am finding it so distressing. How do I really know if I'm worrying about something that won't happen, or is very unlikely to happen. I can't trust myself!
It's very good that you're continuing therapy; it's one of the best things you can do to improve your mental well-being. One of the things you would have learned for psychoeducation in CBT is the recognition of certain thoughts. There isn't some measurement that allows us to really know what's truly
rational or not. Decastrophisation of those events you see, e.g. "likelihood of having to give up my job is high", is quite good for these situations by asking yourself 'what-if' that would happen, then what? Let's you really examine how you've assessed the situation and estimation of it.
Another technique that you may discuss with your therapist is cultivating acceptance towards your thoughts. Using mindfulness meditation can help cultivate exposure to anxious thoughts through acceptance and non-judgmental awareness of your thoughts and its content. This doesn't happen overnight but it's highly useful in managing thoughts that could cause anxiety. A quick judgment meditation (Siegel, 2010) is noted below:
This one usually requires only 10-15 minutes to get the point. Sit down as you would for breath meditation and follow your breath for a minute or two. Then begin to watch your thoughts. Every time a judgment arises, silently label it "judging". Once you're done, jot down your observations about the judgments/thoughts.
Note that you don't struggle to rationalise it or describe it as whether it's irrational/rational - just seeing those judgments as judging and letting them be. Hope this helps.
- Siegel, R.D. (2010). The Mindfulness Solution: Everday Practices for Everyday Problems. The Guilford Press: New York.