Part lease Horse situation gone bad!

I have leased a warmblood dressage horse off my former riding instructor for about 3 years and had lessons off him on this horse for probably about 12 months prior to that. For the last 12 months I have had to share this horse with another woman. There was never any formal agreement made in writing and when this arrangement first came to light it wasn’t handled very well. In fact neither of us really was aware of the other until it became very apparent. Only then was I told that I would be the main leasee and that she did not want to compete so I had full priority and say when it came to shows etc.

Of course things started to change down the track. Firstly when I went away over the summer holidays she took him to a local show which was fine as I wasn’t there. I also had to give up one of my riding days as I live in the city and can only get out on weekends and the odd Friday. A lesson was made for her on a Friday so I gave her that day. Although there was no discussion from him or her regarding this. It just sort of happened. Then we had to both try and juggle our other free days to share. Keeping in mind I only have the weekends to ride and she visits the barn daily after work. She lives much closer than I do and I have to plan my journeys as the traffic is just horrendous and stay for a while once I’m there. I also offered to pay for some of the hardfeed even though it was totally her choice to keep him there as I had previously taken him off site for several days during the week bringing him back over the weekends to ride.

She became more and more involved being there all the time and even started to watch me have my Saturday lessons instead of staying away and giving me my own time and space with the horse. This started to really annoy me and make me feel resentful, anxious and a bit stressed. Then she was started to come and watch me compete at shows also which I found really odd.

Anyway at the end of last season we had done an even number of events each. The Winter was really difficult as in the past I have turned him out for the middle part onto grass and hay due to the lack of grass at the barn property and the cost of hard feeding. But she insisted he stay on the property and be hard fed twice a day. The instructor supported her in this because he wanted to get her money. The horse hated it he was miserable and hungry most of the time as he’s the sort of horse that just loves to be on grass. Towards the end of the winter he got a hoof abscess from standing in the mud all the time etc. which I dealt with swiftly.

The last straw happened recently when we had a minor disagreement on an issue to do with the horse and she ran to the instructor saying she didn’t want to share anymore. To my absolute horror he called me up to tell me he’d offered her a special lease on the horse. Although I can still ride him. I do not know how this came about. The only thing I can think of is that she is out there daily doing free jobs for him. Something I just can’t do but I do my share when I am out
there. I’m so upset that he has lied about so many things to me and also said that I knew that same deal was in place and could have taken it up if I’d wanted it. Which is a total lie and has never been mentioned ever!

So now I’m left wondering how on earth is this going to work out moving forward. If she takes up his offer re the ‘special’ lease I can just see I’m not going to be able to ride as much and I’m sure she will get priority over the shows etc. Why didn’t I actually get this deal initially when I was told I was the main leasee when she first came on board. He has just changed the rules to suit himself without prior discussion or consultation.

How should i deal with this situation moving forward just look for another horse. I love the one I’ve been riding and we have built up a special bond over time and are a good team now and other people always comment on this. I don’t really want to buy my own as I’m thinking I’ll probably only ride for another year or two at the most. I’m mortified my instructor who I’ve known for a long time would behave like this. Although he never has had the best reputation. I thought he would at least have given me first option on this deal.