i can understand in away,
i was a long time virgin and as i meet girls that we wanted to have sex i did find myself fearing sex and stuffed up a few relationship for it
but it wasn't till my current partner that i was able to move past it
it sounds like your fear is from being left alone and the punishments you may get
i would hope your parents love you enough to support you ether way you choose to do no matter what which is apart of th issue that will need to be faced at some time but we can leve that to the future for what is happening now
the way i'd say you'd need an understanding, partner someone that loves you and will support you as you need to take things slowly, not rush you as you need to become at ease and relaxed
become comfitable with each other and play around a bit kissing huging and fondling
it the first step becoming excited to be with that person sexual and more
just take small steps and don't take the next step till your ready as you have to build the fun back and take the fear down you
won't beable to remove all the fear because of the way your parents veiws are but start small is a start