I hate to get all Freudian, but… a lot of the guys I know who have SSA problems have problems with their dads. Either the dads are mean, absent, or have overwhelming personalities that are hard to measure up to. So they are always looking for a father, in the shape of some older man who will give them approval.
There are also some on the other side – they love, respect, and/or fear their moms and sisters, to the point that they can’t even think about being sexually attracted to a girl, or trying to find their own woman to love. So they look for a young, handsome man to give them approval.
If people’s families are part of the trouble, people’s families are not always neutral observers.
But just like some girls go through a phase of sexual uncertainty, some guys get over their shyness or neediness, or get a stronger dose of testosterone as they grow older. Sometimes, they find out they were heterosexual all along. Sometimes, SSA just doesn’t bother them as much.
Of course, that’s not everybody. People are mysterious! But teenagers have so much stuff going on with hormones and brain growth, that there’s no way to really tell how things will work out.
So stick to your guns, but also try to be easy on yourself. You are still growing up and growing into manhood and adult life. You have a lot of stress at home (like all teenagers). When you get older and get away from home, you may even find that things get easier on the temptation front. (Of course, there will probably be new temptations, but that’s life in a fallen world.)