First, I’m sorry about your attack. The odds against it happening again are very slim but it is always good to be prepared.
As for self-defense, Taekwondo will help but, in itself, it is not necessarily the best for self-defense situations. Taekwondo is primarily concerned with sparring, which is controlled mutual combat; there are rules and referees and the goal is to win the match without harming the opponent. Sparring is similar to fighting, since fighting is also is mutual combat, but fighting may or may not have rules and referees, and the goal of fighting is to cause harm to the opponent until he or she quits fighting or is unable to continue fighting. In both sparring and fighting, you have a choice: you can stay or leave. However, in a self-defense situation you cannot leave, there are no rules or referees, and the goal is defend yourself against serious injury or death and to make the attacker stop attacking. In a self-defense situation, you do not face an opponent and then move around and spar or fight. In a self-defense situation, you must react unexpectedly, instantly, and with powerful and effective techniques. Some martial art styles concentrate on self-defense. Taekwondo has some self-defense techniques but that is not its main concern, however, some Taekwondo instructors teach specific self-defense techniques.