Is it my fault?

Okay, well this one is a longen... Please please dont judge me.

Ive lived with my dad now for 5 years, have known his wife and her sons for about this amount of time too.

Me & her youngest son are of the same age. We never ever used to even talk really, and when we did, it was like a geek talks to a popular kid, no real emotion behind it.

Anyway, as the years went on. He started play fighting more with me, and shamless as it is to say, we flirted with each other. It was harmless, im a natural flirt, it meant nothing.

Then one day, he text me saying he fancies me. I said i think hes good looking, and the flirting got more intense.

Then one day, it was my birthday, and i was a little bit drunk, i asked him to get me another beer, he said he would for a kiss... i said no, he got me the beer, then as he went to give it to me, he wouldnt let go. He then pulled me in, and we kissed. It wasnt for very long, and we pulled away because we thought we heard someone coming.

This carried on for some time, and the kisses and actions got more and more intense. He was the first person i acctually did anything with. (not sex)

Then i felt disgusted with myself, all the secrets all the lies, i realised how wrong it all was. So i stopped it completley.

It ruined any bond we had, and we couldnt even get along as step brother and sister. I began to hate him, and im pretty sure he felt the same.

Then he began to beg me to start again, i consisted in saying no, he'd trap me in rooms, forcing me against the wall, trying to kiss me, or touching me, or trying to make me touch him, i'd squirm away and say no.

He's still doing this, only its getting more and more violent, hes not hitting me as such, but if he does hit me, it hurts more than a play fight would.

If he tries to touch me, he liturally grabs me so it hurts, he grabs my wrists and twists them round and then when im close enough tries to kiss me again.

Hes trapped me on my bed, pinned on top of me, trying to touch me, and im still telling him no, screaming no. And he just says i know your lying, i know you, you want it.

Im scared hes going to get more violent, and well rape me.. i wouldnt be able to tell anyone because it was my fault in the first place.

Is it my fault?

I dont wear make up around the house on purpose now, i make myself look like a tramp, i spend all my time locked up in my room.

But then there are days, everyone has them where you just look pretty... and he starts again...

:/ do i deserve it?