submit also your WU receipts as your supporting documents. evidence your bf do supporting you. and presently your income. do you have any finances here in PI or have a good savings? do you have a reason to return here in our country?
Read the link below, i share to you had a related documents on this link, About Entry Clearance Guidance, Wording for Refusal, for a reason you were aware why the refused visas.
http://www.ukba.homeoffice.gov.uk/po.../ecg/vat/vat1/