Anna D

I have been,  trying to break up with him a lot of times but he always play a mind games with me,  i know it sounded like I'm just trying to hooked up somebody who can bring me to usa but that's not my intention,  my ex boyfriend was a mental abuser, that's why I  decided to break up with him,  plus if I'm  only looking for that what's the point of breaking up with him coz in the first place we are already half way through it. I just don't want to be with an abusive man..  

Shouldn't matter at all, should be approved in average time frame as others.

I doubt the second immigrant visa will cause any issue at all
 
Reading the OP sounds like she is from Philippines, they won't give it a mention at the interview if from Philippines

I doubt CO will even mention it

Call or email USCIS and they will give you instructions on what to do.  Let them know you are the beneficiary.

I will first like to say I am sorry that you are in this predicament but I am so very happy that you are able to see sense and break up with this guy. Never talk to him again. There is no excuse for him to treat you badly.
 
Let me just explain how the process works so that my advice makes a little more sense. The US citizen (petitioner) can petition for a K1 Visa for you (beneficiary). The petition will go to USCIS for background checks until approval. As long as it is with USCIS, it really is the petitioner's responsibility. When the petition is approved and forwarded to NVC, it becomes the beneficiary's responsibility.
 
You should not be able to withdraw from this old-K1 Visa that your ex-boyfriend applied for because you are not the petitioner. However, not appearing for the beneficiary interview in the end will mean you forfeit his petition and that should be sufficient. Alternatively, when NVC forwards your case to the US consulate in your resident country, you can call the consulate to request for withdrawal. You will need a number NVC gives to your case for this. This depends on individual consulates. Some do it, some don't. If yours do not, you should just skip the interview. 
 
I believe if your ex-fiancé petitioned in December, you both should receive a reply by September this year. I am not sure whether your new fiancé can petition for you while there is a pending petition with your name. I believe it would show up in the background checks and automatically be rejected which we do not want to happen. Your best bet is to hope that by September this year, you would already have withdrawn from your pending case.
 
Other VJers, I'm sure, have better advice.
 
Cheers and good luck! xx