UK visa denied , need help

[needadvice123]

Hi,

I had a previous UK visa for 6 months and I was invited by a friend of mine. At the time my boyfriend had received a job offer to the UK for a new job but he was not settled. When applying the first time I indicated that I was single because me and him had not been living together for more than 2 years . In the new application, I stated that my bf (unmarried partner - since if I counted the time spent living together in the UK, it was more than 2) was inviting me.
I had all necessary docs for application, but I got rejected on the ground that I did not include my bf the first time. The problem is , had I included him , he would have had to invite me and provide rental contracts which at the time he did not have, as he was looking for an apt.
I stayed at the friend`s house and then when I subsequently entered the UK I always disclosed my real address and I stated I was staying with my bf.
It was stated that me "being a genuine visitor " was in doubt although i submitted evidence of my position. (The document was issued in summer 2010 but it stated my position till 2013). Maybe I should have taken a more recent one.
My question is: when do I reapply for a visa? What to do in order to increase my chances of receiving it this time? What are usually the consequences of a rejection? ( Please note I received a rejection, not a ban on reapplying)?
The letter stated that I should have said that i was not single at the first application, but I was (according to their definition of unmarried partner). Also please note that I didn`t apply for an Unmarried partner visa which would give me work rights but for a simple visitor visa.
Let me know if you can help.
Thanks