Most tribunals will wave the fees if they truly cannot be afforded, and the husband’s involvement is helpful, but not necessary. Also, unless you two are engaged in sexual actions then you have no reason to abstain from communion (unless you’ve committed some other mortal sin, of course). It is not a mortal sin to be divorced, especially if the relationship was abusive. As long as her conscious is clean on other grave matters then she should embrace the healing power of the sacraments ^^ Now, if you’re engaged sexually then both of you should be abstaining from the sacrament.
I would really encourage her to speak to her pastor about the financial burden, and then proceed with the annulment process. Her husband does not have to have anything to do with it, an annulment can be obtained with or without the other spouse’s cooperation.
May God bless her for her desire to keep the Church’s teachings, and grant her a just ruling on her annulment.