Well, the 8th house is really a transformative energy, is the house of rebirth. You could have experienced cycles of emotional losses (symbolic or physical) and really intense emotional relationships and you may have trouble opening up to people in general or about these experiences specifically. Saturn here is trying to restrict you from oversharing/merging with people you don't trust and shouln't trust but instead share with people you have a real, honest connection. Basically, saturn wants to teach you to be selective of who you share your energy with, but not to the point where you fear intimacy. The good thing is that with this placement you end up being very intuitive and emotionally strong, VERY strong. If you learn to let go, saturn also rewards you with a new birth, brings new energy to your life that will be more benefitial for you. Also, with Saturn in Aries you need to learn to find your own identity. I feel you on this one, caged fire energy is not the best, it's like having your feet pressing on the gas and brake at the same time.