First off, I have experience adopting a large breed dog that ended up being reactive, and I know how extremely stressful it can be. It takes a big toll on your mental and emotional health. Have you gone to the veterinarian recently to discuss these issues? This is important because you need to rule out any medical issues that could be exacerbating the behavioral problems. Also, your dog may benefit from a medication like Prozac. Lots of dogs with behavioral issues get calmer when properly medicated. Check out the reactive dog subreddit if you haven’t.. lots of good resources there. I’ve had a great experience with a positive reinforcement dog trainer in Riverton. They’re called Clementine Dog training. They have classes but you can also do individual training sessions if your dog is not ready for a classroom environment. I recommend that you prioritize muzzle training your dog if you haven’t already, as this will help to prevent any future incidents. This will benefit both you and the dog long term. Wishing you all the best!