First of all, let me say that I am very sorry you are going through this! It's intensely disappointing when our bird falls in love with somebody else and, because they can't be with them all the time, takes it out on us (they always seem to blame us for their beloved absences even if it's not our fault at all!).
The good news is that yes, there is hope! Maybe not hope that you will become 'the chosen one' but definitely hope that you can become a flock mate he likes and respects. The key to this is the following:
1. The bird cannot be overly hormonal because, if he is, there is nothing on this earth that would distract his one-track mind. In order to achieve this, you need to make sure his diet and light schedule are appropriate - and you are in luck because, as the days are getting shorter, if he is kept at a strict solar schedule and you reduce protein intake after he finishes his molt (which should be almost done), he will stop producing sexual hormones very soon.
2. You can't ask for anything. You pretty much need to be his slave and expect no payment
In time, he will calm down and begin to ask for your attention -this is inevitable because they NEED the company, touch, attention, etc and, been pragmatic as all animals are, if he cannot have the one he loves, he will love the one he has.
3. A good full spectrum light (CRI 94+ and Ktemp closer to 5000 than 5500) - the good quality light will allow him to produce happy and reward hormones which will put him in a good mood.
4. Strict routines within a strict daily schedule -always the same thing at always the same time of the day -note that I say 'time of the day' which does not mean the time by the clock, you go by the sun, instead. It also means every single day, weekdays, weekends, holidays, etc. For a parrot, there are no exceptions, every day has to be the same -it helps with anxiety and stress which influence mood, too.
Then, when you have him at the resting season (no sexual hormones) and he has gotten used to the daily routine and your not really asking for any physical interaction, you can start incorporating a short routine of target training (always using a high value items as reward but also using them previously as simple friendship tokens).