If it's any consolation most PhD students hate writing up as well. The difference is, that after three years the style will be more or less second nature. Your problem with 'borrowing' from reference sources will also reduce, as your own knowledge of the subject will make it much easier to express things in your own words. Ordinarily we would advise anyone who is in two minds about whether to do a PhD to do something else. However 90% of your PhD will be spent in the lab and the writing skills will probably come with time.