a girl who claimed she would keep my mare in the show circuit as she was incredibly talented. She didn’t, but I don’t really have a problem with that because she says she has a good home regardless. I know where the girl boards my horse, and after I sold her the girl promised I could come and visit anytime.
She said she would keep the mare in the show circuit. She hasn’t, so either she meant it and changed her mind, or she didn’t mean it to begin with. Did she promise to keep showing the mare, the same way she promised you could come see her?
If you know the barn, and it’s a public barn, I don’t see anything wrong with dropping by to see the mare. If the BO or BM questions you, you could smile, introduce yourself, say you used to own Lady and were in the area and just wanted to drop in and say hi to Lady. Or however you would word that. “Hi. I’m emilawrence. I used to own Lady. New owner told me I could come see Lady, I was in the area, so I thought I’d drop by. I just wanted to see her.” Not “I just wanted to see how she’s doing.” If it’s a public barn you don’t need permission to go there. If you run into the mare’s current owner, do the same thing, smile, say “hi, I just came by to see Lady. Thanks for saying I could come see her. Wow, she looks great!”
In your OP you said you know where the girls boards your horse. I know you know she isn’t your horse now.
Do you really just want to see the mare? Will you be content with just one visit? Will seeing your mare, even if she is doing great, make you feel good? Or bad? Might not be a bad idea to ask yourself that. Then, if you want to see her, go see her. No need to text her current owner again.
Don’t be scared. You know you aren’t stalking.
ETA: I used to ride a horse. I didn’t own him, he belonged to my family. He was retired, and I moved away. If I were to go back to that area to visit friends, and I knew the barn where he now lived, and it was a public barn, I’d drop by and see him. I wouldn’t feel I had to ask the new owner’s permission, or the BO’s or anyone else’s. I loved him, I rode him, I took care of him, I’d go see him as I would any other friend in the area. If he were at a private barn and I had contact info, I would call the BO and ask if I could come see him while I was in the area. I might be a little nervous, but I wouldn’t let that stop me. Would it make me happy to see him? or sad? I don’t know. I’d just want to. 