Dream Analysis: feelings

i had a dream that i was walking with this guy ive been talking to for a year and a half and my sister was there too and they were flirting and i was getting at both of them i was walking behind them and them he got hit by lightening or something and he died and i was crying so much because i never told him how i really felt about him.
I really havent told him how i felt about him in real life and he does flirt with other girls on myspace and i hate it and i always question if i should trust him, my sister is also i flirt and i dont trust her.