HELP: engagement legal paper instead of marriage paper?

I've got a problem. I have been in a close relationship with my girlfriend for just over 3 years now. However, she was a foreign student and her student visa expires at the end of January next year. I do want more time and her to stay in UK (not US, etc. btw).

The only thing that can make her stay here is marriage or some legal paper. We have both talked about this issue. We both see that a white church wedding is not ideal right now due to financial status, career, etc. Am in my mid 20s and she in her early 20s. We want a white church wedding when we are both over 30 and both have hard founded careers, and lots of money, etc. The dilemma is, how can we both keep our relationship inside UK (keep her here legally), without a full blown marriage?

So am wondering if anyone is knowledged with "getting married", "civil procedures (marriage related), etc. Am wondering what we both need to do, and whether it's possible getting a legal paper from the home office.

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try this website - it may help you. Otherwise you can ask advice from your local MP.

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she could apply for a work visa, to replace her student visa(if she has a job)

marriage is the easiest way and safest way. my boyfriend and i did it just so he could get his permit in my country incase we decided to stay here (because we like it a lot) after his yr of schooling. he got it within 3 months and now we have all the options open!