Don't worry - you're still in the very early days of rehab. I'm afraid it will be a long time before you can start Taekwondo again (it's so incredibly important that you stick to the rehab protocol and timeline that your surgeon gave you) but the good news is that the vast majority of ACL surgeries are very successful, and you should be able to go back to sports and build back up to your previous level once you're fully recovered.
I sympathise a great deal with your situation, as I'm a passionate skier and I also had to sit out of my sport for what felt like forever after surgery. I returned to skiing after seven months (so roughly the same timeline that you've been given for Taekwondo) but to be quite honest, it was a full year before my knee started to feel really "normal" again. The good news is that this winter is my second season back since the surgery, and my knee has held up fantastically; I no longer wear a brace, the knee is feeling great on the slopes and on jumps, and I've been able to get out into the backcountry and ski harder conditions than I did before theinjury.
I'm afraid you're entering the really frustrating part of recovery, where you've been working hard and things are getting better but "normal" still feels a really long way away. It lasts a while, but keep plugging away at the rehab and you will get there. Straightening the knee is actually more important than bending it fully at this stage; full flex can take a long time to come back (months in my case) but full extension is really important to be able to walk with a correct gait. Make sure your physiotherapist is working with you on flex and extension exercises as well as the strengthening.
Best of luck with your recovery! There is a light at the end of the tunnel - it just takes a while to reach it.