Miriam had a blogging crisis (sv) after friends began asking her questions like Who are you blogging for? and What is the purpose of the blog?
I think her inclination to 'just' write about things of interest to her is a good one as the best blogs are more driven by the blogger's willingness to say something interesting than a desire to make the audience happy. Personally, the tricky thing for me with blogging the last year has been to find a good tempo (i.e. interval between blog posts) for blogging, resulting in quite some time in-between original posts as it is very easy not to blog once you started to blog less.