So my step dad had been in my life since I was 4 I call him dad I dont think if him as my stepdad hes just my dad I call his mum (grandma) i call his sister (my auntie) and they think of me as his daughter well his son ( who I have never met because he lived with his mum but now hes lives with us) came down round about Christmas time so we have got to know eachother and we share a room because we are " family" well I have started to catch feeling for him and he likes me to. we are 17 btw and we dont think of eachtoher as brother and sister but we have the same dad and grandma and auntie and it's just weird so I said we cant act on our feeling because that's just weird well one night on valentine's day our dad and my mum went out on a date and I was working late and I came home to rose petals all over the house and I thought it was my dad doing it for my mum but nope he was the only one home and he gave me flowers and drew me a bath with bubble and rose petals in because he knows how stressd I have been anyway I got out the bath and I told him to get out while I get dressed because we share a room and he came over and took my towel off and we had sex WITHOUT A CONDOM and omg it was so romantic he told me how gorgeous I looked even tho i had no make up on i just came out the bath. he was kissing my neck. every second asked me if I'm okay because he knows it was my first time and after we was done he gave me a back rub and played with my hair until I fell a sleep.. I woke up the next day in a panic because of the rose petals everywhere but nope he cleaned them all up and my mum and dad never knew they asked how our night went and I said I worked late came home and went sleep.. after that I went back to my room to just watch tv and he came in and kissed me and said" good morning how do you feel are you sore or anything do you want me to turn the shower on " and offered to buy plan b or come to the doctor to talk about birth control.. I said I'm already on birth control because my period are heavy and painful and he smiled and winked but he just soo so so sweet and I just dont now how to tell my mum and dad.. I think I'm in love with him and I just cant be.. is this wrong

****** update

So I know this is wrong guys I know but I think I'm in love hes so sweet the other night we went on a date to the cinema and we just sat there holding hands and kissing when we came home.. my mum picked us up because she thought we are in to the same movies and bonding time is in important.. any way and when we got home we fell asleep in my bed together arh he so handsome but one night he went out with my dad well our dad and me and my mum had girls night and she said how are you and *** getting on and I blurted out that we are dating and we slept together because I felt bad and she said it's so wrong we are like brother and sister and they we need to change rooms now.. she told my dad when he got home and he had a massive go at us when they all calm down *** spoke up about how he really does like me and how he thinks this could go some where and now we are both grounded how fun.. but we still share the same room for now but I think they are making him move in the down stairs room soon but I dont want him to... I dont know it's all one big mess but we told them we are not braking up and they understand that but we just cant share a room anymore.. but they also said that when we turn 18 that we could move in to the summer house together and I'm soooo excited for that... btw we are not grounded because we are together we are grounded for not telling them in the first place.. my dad and mum said if you was honest I'm the beginning they would have been okay with it and moved on.. any way it was a very good ending.. 😁😁😁