Got an Answer?
Breathing. Regular yoga. Counselling. Exercise. Facing your fear straight up and identify why she is intimidating, she is probably overcompensating for her own fears. I have step kids and used to get so anxious before they would come until I realised how normal our home was for them. They love it here and have a lot of positive things to say/do/feel here. I spose my fear was being inferior. But you're a step mum, its different to mum and there are positives. Focus on those.
There is this video going around you can watch to control your breathing and refocus your mind. Works like a charm!
I agree with some other comments, it's all about getting yourself out of your head and back to reality, being "present" in the moment. Stop focusing on the stuff running though your head, all the stressful thoughts and "what ifs" and try and conciously focus your thinking on what's going on around you.
Can't your husband/ partner pick them up after work for you? I can understand your nervousness it could be an uncomfortable situation.
Check out this website. There is a technique to centre yourself. It's basically just mindfulness, which is simply getting you to be in the here and now instead of stuck in your head.
I find it helps to concentrate on keeping my breathing slow and even. The muscles in my neck and shoulders tense up when I start to get anxious so I deliberately tense them as much as i can and release them, concentrating on the relaxing feeling when they're released and song as you're driving to get them blast some feel good music and sing along.