I'm 19, I started my period when I was about 13. The thing is I've never had a regular cycle. I'm aware it can take years to settle down, but after 6 years and no pattern what so ever, I'm wondering what's up. Sometimes I can go about 56 days with one, then sometimes it can be as little as 5 days. The thing is I'm usually on for 7 days so at times I may only have a day or 2 off before I'm back on again. I've just settled down in a relationship, and its obviously going to effect my sex life. If I went to the doctors would they put me on the pill, as I've heard this would correct the abnormal periods, by making them regular and I guess it would help with the sexual activity as well? Any helps muchly appreciated

This can occur for many reasons, but yes, most likely they would put you on birth control to help regulate your periods.

Well, taking the pill can help regulate your periods and be a helpful birth control (although it is not 100% effective)
With your periods the way they are now, you may not know when you are most fertile. Not a great thing NOT to know when you are sexually active.
Have you ever been to the doctor? A normal cycle is 19-35 days. So, 56 days is way to long and 5 is way to short. You really should get checked out by a doctor. Even if you were having normal periods, you should go.