I've been struggling with this for about five years and I don't know how to handle it.

My parents split when I was 16 and after many suicide attempts, my father got healthy and met a nice women. She has two children, a girl who is one year older than me, and a boy who is a year younger. When my father was first dating her I never saw her kids because I was never around enough and neither were they. My dad and his girlfriend got engaged and decided to build a house together. After a few years, the house was built and they moved in. By this time, myself and the boy were in college and began seeing eachother during holiday times when we both had off from school. There has always been sexual tension between us and one night we were watching tv and he held hands. I had always had a little crush on him but never thought it would go anywhere. Nothing happened more than just holding hands, but the tension built. I thought not much of it although my crush on him never went away. I had two serious boyfriends since then and one so serious that I almost moved accross the country to be with him. Right before I was to move I visited my future step brother and we kissed. I brushed it off as he was going to miss me and gave in a little to the tension. I ended up not moving and breaking up with my boyfriend. Since then my relationship with my now step brother has become very physical. Whenever we are at the house together we become physical.

We have discussed how we like eachother but he just can't get passed the fact that I'm his step sister. Our parents know that we like eachother and encourage it, as they have always seen the attraction between the two of us. We are both adults and out of college and I am beginning to realize that I have loved him since I met him. We in no way grew up together. I know it's more than just physical but I don't know if I can convince him, or get him to be willing to give us a real shot. It is so obvious when we are around eachother that we genuinely love eachother. Even his grandparents (my new step grandparents) asked if we were dating by the way we look at eachother and the way we are around eachother and they also fully support us.

I know the odds are stacked against me and I feel there are only a few outcomes to this.

1. I stop myself from being physical with him because I want more and he can't get passed it. If this happens I feel like I will just suppress my feelings for him and it will take a lot for me to find happiness with someone else and I will always long for him (as I have been for the past 5 years.)

2. I pursue him and either it works out between us and we as a couple are accepted by others, or it doesn't work out and I realize that it won't ever work.

I dont know what to do.