Refusal of a UK visitor visa

[Beiar]

I am a nineteen years old student from Ukraine. I have got a girlfriend in the UK, I met her in February, 2016. She's visited me four times since. Last time she was here she invited me to visit her in the UK. I decided to go this summer for 20 days. I submitted an invitation letter from her. It tells our story, how we met and the list of her supporting documentation such as:
• a copy of her passport confirming that she is a british citizen;
• another copy of her passport showing that she's been to Ukraine (stamps at the border);
• her payslips from work and a bank reference showing that she can support me in case of emergency and her home address;
• her letter from uni showing her home address;
• her tickets, insurance, booking confirmation letters for Ukraine, again, showing that she did travel to Ukraine;
• two photos of ours;
She also wrote that I would not need money for accomodation and food since I am staying with her at home. I have also submitted my cover letter telling our story and supporting documentation:
• reference from my uni confirming my status as a student;
• my student ticket confirming the same;
• tickets to the UK and back;
• my travel insurance;
• my birth certificate (showing that I am my father's son) - to prove that I am related to my sponcor (Dad, who is living in Ukraine). Therefore it's obvious that my sponcor is my Dad, not my girlfriend. It is clearly stated in my online visa application!!!
• photos of me and my girlfriend ( we had 4 photos overall); And my sponsor's(dad's) supporting documentation:
• his references from work showing his occupation and wage;
• his references from banks showing that he will sponcor 1000 pounds on my trip;
• a copy of his passport;
AND YET, lately, I have been refused of a visitor visa. Here is their explanation: I have refused your application for a visit visa because I am not satisfied that you meet the requirements of paragraph(s) 4.2 of Appendix V: Immigration Rules for Visitors because: You have applied for entry clearance to the United Kingdom to visit your girlfriend. In order to assess your application it is important to see evidence of your overall personal and economic circumstances at the time of your application. Supporting documentation allows me to assess whether your statemens on the visa application form are a true description of your circumstances. The onus is on applicants to ensure that they submit adequate evidence of their circumstances and ability to finance their stay in the UK/ YOu have stated that one the reasonsfor visiting the United Kingdom is to visit your girlfriend. Allthough you have submitted an invite letter you have submitted no evidence of communication with your sponcor. Given that visiting your friend is one of your main purposes of your travel. it is not unreasonable to expect to see some evidence of your relationship to this person. However, you have chosen not to provide any ecidence which might demonstrate that you are close friends such as photographs and that you have met this person and are in regular contact. It is unclear from your application how long you have known your stated friend and there is no evidence that you have ever met. I note that you have never traveled to the UK before and there is no evidence that your sponsor has ever travelled to Ukraine. It is unclear as to the exact nature of your relationship and why you have chosen now to travel to the UK. In these circumstances, I am led to doubt a genuine relationship to your sponsor which reflects on your intentions in both travelling to and departing from the UK.
I can understand that you brits don't like Eastern Europeans and so on, but it is just preposterous, isn't it? The funniest thing: they said that I had not provided photographs and guess what? I received my provided photographs back in the envelope where the refusal letter was. And of course there's no option to appeal or have an administrative review. YAY!