Sexually confused help! :(?

About six weeks ago I just lost my interest towards females I've been straight all my life and still am I mean my attraction came back and I started to feel like me again... But then as time went by I began to feel depressed again as I was unaware to why/how this had happened. All I want is my life back I just don't feel like me atm I'm unsure to why this has happened but I started to get these intrusive gay thoughts and I can't read between the lines and ask myself WHY? I just want to feel like me again and this sexual confusion is ruining my life... My mum is an alcoholic however I live with my dad so that's not an issue, I just want to be able to get my life back on track and clear my mind of this negativity however it's very difficult. I'm 16 so I'm going through adolescence and all. But I just can't understand why I've lost interest and attraction towards females... All I want is to be able to get my life back on track. When I'm alone with a female I do still feel attracted and when I'm at a night club I'm ok. I just can't understand what the trigger of this is and why it's happened to me. I just hate my life atm and i just feel suicidal as I hate feeling like this. Please help much appreciated x