Jenna,
First off it sounds like there is more going on then a defensive or pre-emptive question can answer. As I am not looking to get into your personal life I will wish you the best, and hope this can help you out in pondering your options.
In many martial arts, there is a teaching of self-defense or non aggression. That the art is not supposed to be used unless one is defending themselves.
This is good for most people and also helps to build better moral character.
Yet when on the street, and you are in it and unavoidable then sometimes a posturing attempt or pre-emptive strike is in order.
But is this not against the inner peace to be taught of the art one studies?
Yes and No.
You are in a spot you have one guy in front of you with another just off to his side. The one in front is tall and is taller then you while the second guy is much shorter then you. So while the first guy is posturing and getting in your face the second guy is there to make the sucker punch. (* Yes I have lived this before

*) Well as I was telling the taller guy to go for it, in essence calling his bluff and posturing with my own posturing, the second guy balls up his fist. (* One must be aware of your surroundings. Do not tunnel vision in on the immediate problem for other problems will sneak up on you and make it worse. *) I reach out and slapped the punk acros the face. Yes I reached out and slapped the punk across the face. This brought my hands up into a more defensive position and a more aggresive posture if you will. The smaller punk yelled, "You hit me!, I am only 17, see this guy hit me and I am a minor." Before I could speak another man in the crowd spoke out and said, "I saw a man ***** slap a boy for trying to attack him."
The crowd was on my side now as I had not devastated anyone but shown I was willing to make contact, and was not backing down.
They postured some more and yelled but they had stepped back away from me and were heading towards their vehicle.
After they left a young man asked me why I let them leave after calling me all those names. I replied, "They are gone, I am still working here. I am not hurt. There are no police involved. and their name calling did me no harm."
So the pre-emptive strike even though was not a strike to take them out permanently it was still a pre-emptive strike for contact had not been made.
Yet I argue that the moment they declared their hostile intentions toward me, they had lost concern for issues such as is it right to pre-emptive strike or not.
I made a lot of decisions like this. I had to decide instantly if such a move would end it now or if it would make it worse.
In another case, one guy hit himself in the chest while yelling, "Are you Talking to me?". He then hit himself in the head. This is to bring is adrenaline up and get edorphines running so he will nto feel my counter shot if I get one after he attacks me. Well after his second attack on himself, I popped him in the nose and front kicked to the groin. I replied. "Yes I am talking to you. Next?" (* Yes a little arrogance and also posturing to his friends to let them know I was waiting for them to move. *) Once again contact made to him before it was made to me. But I knew the fight was one, it was a matter of time and his choosing, so I decided to make it a manner of my time and choosing.
The problem with this is that one has to be willing to follow through with the posture or the minor pre-emptive strike with all out strike warfare. If anyone is not ready for that then it is something I believe should be avoided.
Now all my stories are not this lucky or this one sided either.
There once was this group of ten guys who were bother and one might say assualting a female employee of mine. I aksed them to leave and ave them room to walk out. They stopped on the way out, and went after another employee. I stepped up and told them to leave again. (* They had all lost sight of me. Fools *) So we get out side and this guy starts running his mouth, and makes the comment that, "Ill be back!" to which I replied "Dude, you got ten guys and just me, if you cannot take me now, do not come back when I wil ahv friends and back up here." He had his hand in his pocket and was about 6 feet away with one of his friends almost in between us. The barrel of the gun became real evident in his baggy pants as he pointed it at me through his pants and was pulling back to clear his pocket. I could not reach it to keep it in check it was already pointed at me. I grabbed his friend and did a body, neck lock to use him as a body shield. His friend is screaming I was going to break his neck. Not that possible where I was at, but he did not know. So he said, "put the gun down."
Not fun staring down the barrel of an auto pistle.
I yell for the guy a the door to close the door and be inside and lock it. Also to call the cops and ambulance. (* I expected I would have needed one, but was still trying to limit the colatterial damage done to others nearby. I was the fool now. *)
After what seemed liked forever (* have someone mad at you point a load gun to your face area even if you are hiding behind one of his friends, each second is way too long. *), but was most likely a minute at best, the guy with teh guy put it back into his pocket pulled his hand out and they all went to their vehicles. I let the guy go once there were large obsticales between me and the guy with the gun. The guy I was holding had jeans on that were tight and a tight shirt, and I had been real close to him so I knew he did nto have one on him. They get to their cars and then roll to leave, but stopp just before leaving and ask me if I want to go now? I tell I am going to kill you! as I charge the truck he is in, with three guys in the front and he is straight in front of me. I moved to his back side swinging a set of keys to hit his hand if it came out the window while tryng to just the "B" pillar of the cab as cover and also prohibit his movement. The drive of the truck was more concerned with the paint job of his truck then seing me get hurt, so he took off out of the parking lot and through the ditch.
I got lucky and survived. That guy had a bigger posture then I had on me. Not sure if he was willing to bring it , but it is too easy to make a mistake with a 7- 15 lb trigger pull.
I have other stories where I survived, but got beat on, although I brought it to them at that point. Even with 5 or 6 of them I would take it to them with all I had.
So, it gets better with experience, but you need the experience and mistakes to get better. Not recommended for survival, yet if the situation is much different they dealing with gang members or street thugs, then one can read reactiosn accordingly, and take a guess there.
So yes I believe in the pre-emptive strike for this reason and also from my experience I got hurt less in the long run even with those big scares and when things went bad. But I knew that possibility when I stepped into it.
I am not sure if any of this helps. Good Luck
Just remember: "If you choose not to decide, you still have made a choice." Rush - Freewill