Hello didireally,
I am sorry that you are in a position of worry and fear at the moment. It is not clear from your post whether the person threatening to blackmail you is someone personally known to you; a regular (but mean) person you have met online; or whether it is a scammer who you have never met, but have confided in and/or had cybersex with.
Here, we can only give advice regarding scammers - we are familiar with the ways (and threats) of scammers, but we are unable to help with people's personal relationships, or cyberlovers.
Have a look at this Basic Guide to Scams, here:
viewtopic.php?f=3&t=5for help in determining whether it is a scammer you are in contact with.
If it is not a scammer who is threatening to blackmail you, I think you will need to talk to and seek help from someone closer to the situation - maybe a trusted friend or relative, a religious leader, a local advice centre, a marriage guidance counsellor - and, of course, the police.