Your options are very limited. Your overstay is grounds for refusal for all visas except those relating to your marriage or long term relationship (ie 2 years cohabiting) to a UK national or person with indefinite leave to remain. Even then as you are here illegally the UKBA would require you return home and make your application from there, though they would not be able to rely on the overstay alone as sole grounds for refusal.
Your girlfriend would only be able to apply for ILR after ten years.
You cannot apply as a dependent of your girlfriend because you are not married to her and even then it would be legitimate grounds for refusal.
There do not appear to be any grounds for an Article 8 RIght to Family and Private Life discretionary application.
You could attempt to make an application for asylum but it must be genuine. IN order to be legitimate you must not be able to return to your home country because you have a well-founded fear of persecution because of your:
- political opinion; or
- membership of a particular social group.
You would have to prove the above by using documentary evidence and if your claim is found to be spurious then this could affect any future application you make. In reality less than 20% of persons claiming asylum are actually successful.
You can only claim ILR on the basis of long residence if you have been here illegally for 14 years so obviously you're a very long way off of that.
Sorry it could not be better news.
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