Sorry to hear you are having issues with these sort of attacks, they are, as mentioned above, part of Open experience some like it, some hate it, but it is OPEN!
Going to Solo or a group is the perfect answer and will instantly stop these sort of encounters. However if, like me, you want the Open experience and the adrenaline buzz, then you have to try learn the evasive action. If they do interdict you in the ship you are describing, basically you will lose, and credit to you for not combat-logging.
The way i always approach this type of game play is to beat them in supercruise, not in normal space where their weapons will shred you before you can text 'Why are you doing this?' Press the keys 'Ctrl' and 'B' whilst in game and it will bring up in the bottom left corner of the screen a 'Bandwidth monitor'. This very basically shows you network traffice coming into your PC and leaving your PC. BEFORE you jump into a system if the send and receive numbers start to SPIKE at above say 1000+ and continue in this high or go higher it means your PC is contacting another players PC to bring you together in the same instance.
So now you know to expect other players when you drop into that system, armed with this knowledge expect the unexpected, and immediately look for hollow squares or worse hollow triangles, turn toward them and pick up speed. lock the hollow icon on your sensor so you can see his/her ship and watch it's flight path. As you pickup speed, watch to see if this target turns to get behind you which is the position you have to be in to make an Interdiction attempt. You will (Should) be going faster than this target by now so they cannot interdict you untill the distance tween you starts to decrease so as long as you don't slow down or turn sharply they will always be behind you with the distance tween your ship and their ship growing you are safe.
This will give you an indication if they are after you or not, if they keep following you when there is nothing in the direction you are heading they are after you. They will never catch you as long as you are not heading towards any Planet, star ot other object which will slow you down, maneuver your ship to head into deep space.
One of two things will happen next.
1. They will give up the chase as you pull them further and further away from their hunting ground and they will give up the chase they cannot win.
2. They keep following you, in which case you High wake out and have a rethink on you getting into that system (Going to try again ot going into Solo/Group and then trying again). Ig you choose a high wak option, make sure your intended system you are jumping to is in front of you and not behind you in ANY way, as if you turn to line up you may come within their FSDI range and Bang they have you!
The above all depends on out thinking the cmdrs and being quick in your decision on what you do when you drop in. This is where the bandwidth monitor is SOooooooooo useful not only for the attackers, as they can also see you approaching on their monitor as much as you can see them whilst you are approaching. So if you see this rise on the start of the drop in procedure, BE AWARE and BE READY.
If you are in a bad position with hollow squares/triangles all around you when you jump in, come to an Immediate stop, and drop into normal space, make sure speed is at minimum and whilst the 10 sec FSD cool down is happening, go to the Nav panel choose another system and high wake out. The aggressors have to find your wake signal and approach this. This period of time in them dropping on your wake signal should give you enough time to cool down, plt your next jump and activate the FSD.
As you get more experience at this procedure, you can play with them a bit, bring your throttle to just under the shaded area on the throttle indicator, initiate your FSD and line up with your next jump and it count up but you will not jump as you are not going fast enough. Have your finger hovering over the boost button, and as soon as the aggressor jumps in, YOU BOOST and you insta jump leaving him/her stranded whilst they cool down. they won't have time to do anything.
This last bit needs a bit of practice, but it is my fav why of avoiding these types of incidents. I even do this but low wake instead of high wake so i jump back in the same system and head towards my destination. I count 14 (Their cooldown period and their FSD countdown), then just as they pop up again i am at idle speed and i drop down again and repeat the procedure. Its amazing how this really really annoys them. A word of warning......you must practice this as timing is critical in getting this to work, and it won't work if they are in a group as a wing member will be waiting for you to pop back into supercruise and they will nab you. Thats where experience come into it.
TL; DR.......
Bandwidth Monitor...USE IT.
Practice watching what their ships do.
Fly towards them and past them.
Get up to speed as soon as possible.
don't head for any star, planet, or other gravity item which will slow you down.
Practice again.
You can have some fun with these people and laugh at the abuse they send over the ingame comms
Fly Safe.
