I'm going a little bit away from what everyone else is saying, so ignore me if you want ;)
I think that the biggest problem for most people is that they expect the bond to be the same, no matter what horse it is. After feeling that first significant bond with a horse in the past, or even one that you're working with now, your mind immediately goes 'oh wait, it doesn't feel like this when I'm working with ____ but it did/does with _____. _____ and I must not be bonding!'
In reality though, we have to realize something. We can not expect the bond to be the same between different horses! As an avid equestian, I'm sure that you've noticed that no horse has the same personality. Some of them thrive on human contact, some don't. Some love to work for you, some don't. Some of them are curious, others don't really care unless they are in danger. That is what makes horse ownership so amazing. Part of owning the horse is discovering it's personality. I venture to think that their bond with us must be different as well, depending on their personality, your personality, and how they 'mesh' together.
For example. I have a miniature horse mare named Sour. Sour has an EXTREMELY alpha-mare personality, and she is the opposite of touchy-feely. There is no end to mare glare faces if I try to brush her or love on her for too long, and she has no interest in just hanging out with me. That used to make me think that she hated me, and that we would never form a bond because she just plain didn't like me. This seemed to be confirmed by her agressiveness towards everyone. After years of battling her with personality and clashing with her though, I realized that all she wanted was a job. After I gave her one (driving), her personality did a complete 180, within just a few weeks! She still hates being 'loved on' and doesn't particularly enjoy company if we're doing nothing, but she and I have a working bond, and it is perfect for us. We 'bond' by learning new things together, and she loves it. She went from impossible to catch to being the first in line to be caught. It was insane. She is a VERY intelligent animal and wants to use her brain. But if I don't give her a goal or a job, and I am not 100% clear about the fact that I am in charge, she'll spend all day challenging me for my position and being a complete witch.
Opposite of that is the foster filly I'm working with. Long story short, I pretty much saved her life and she sees me as her 'protector.' She's still a baby, so there is no room for a working relationship like the one I have with Sour, so I figured I wouldn't bond with her. Wrong. Instead of a working bond, we have a 'provider' bond. Kenzie is a bit of an airhead at times and she's quite spooky, but she recognizes me as her supplier and as the person that can make things better. It is not in any way the same to me, and it took me a little while to realize what it was, but its there.
I didn't say any of that to guilt you about the idea of selling Ronan, so don't take it that way. I just think that it is good to just make sure that you aren't overlooking an already existant bond, maybe because you are comparing it to the one you had with the stallion.
After thinking about that, if you are still not happy, thats ok. Sell him if you feel like its the best idea, and perhaps look for a horse that can give you the same bond that the stallion did. Just realize that you might never find it, and its a risk you would have to take, because bonds take time. You might loose what you DO have with Ronan and never find 'that' horse that can give you the bond type that you want. Opposite of that though, maybe there is the perfect horse for you, waiting for you to find it. Its just one of lifes gambles, and you have to decide whether you want to play or not!
Everyone in your life is meant to
be in your journey, but not all of
them are meant to stay till the end.