hah, hmm, I guess my advice is not so much use to you then
Consider the group once you get some confidence up. Depending on the group there are often runners of all abilities, so no doubt you will be able to find others to run with at a pace you like. There will always be someone there to drag you out when the weather is like today and you don't want to go out.
Good luck with your training. You could always try starting a training log here to see if that gives you some motivation. You could also give one of the many available on line training programmes a go. There are endless free 1/2 marathon schedules you could download (across all abilities). Having such a schedule can also help with motivation. I suspect they must even have some on the Wellington half page.