Getting married to your Thai girlfriend
Getting married to your Thai girlfriend will not make it easier to get a Settlement visa to England. Of course it is not possible to get a settlement visa unless you are married; however the embassy will require that your relationship is of a certain length.
If the only reason you are planning on getting married is to get your Thai wife back to the UK, stop and think. If you are not able to get a UK tourist visa for her to visit you in England, how are you going to get a Settlement visa?
If you have known your Thai wife for a small amount of time and are applying for a settlement or marriage visa, it will look like a marriage of convenience, a marriage to allow the Thai national into England to work and earn money.
One of the main reasons why Thais are refused a visa to England is because they apply for the wrong visa.
The immigration department is more visa friendly with relationships that have been built up over time and are more likely to give a settlement visa after a tourist visa has been issued.
If your Thai wife has not been to the UK, it is always best to start with a tourist visa. When a tourist visa has been granted, it will give you credibility when next applying, proving a relationship will be that much easier. Of course each visa application is individual, with a decision being given on its own merit. Start off with the correct visa and over time your Thai wife will be in the UK living with you full time.