It is always hurtful, no matter how old I get, to receive feedback that I don’t want to hear. While I would normally agree with everyone that says make this friend an ex-friend, I would also add that everyone is entitled to an opinion. Did you ask you input? If so, some people don’t sugar coat things, they instead say exactly what they’re thinking. If you didn’t ask for an opinion, I would agree that it may be time to add this friend to your ex-friend list.
I can honestly say I’ve been on both sides of the fence, with someone giving unwanted feedback without being asked, as well as someone giving feedback I asked for, but at the same time something I didn’t want to hear.
Everyone has different taste in horses. Some people are also more brutally honest than others. It is okay to have differing opinions with friends, but it’s also okay to choose to not be friends with someone who has a different opinion than you.
I don’t think your horse, based on that one picture has a spectacular jump, but he has a safe, decent jump for a jumper.