OP,
This is more about deciding what is important to you in your life. Do you want to grind with 70 hour work weeks and have wealth? Or do you want to cultivate relationships where you get meaning from said relationships but maybe don't have quite the financial wherewithal that you would if you worked more? Like others have said, there are limited hours in a day and limited days in our lives and everything is a trade-off. Time is precious.
To answer your original question - yes, I have sometimes felt like being in a relationship holds me back from my individual purpose too. It is easy to get a rut in a relationship whereas when you are single with complete freedom you are much more likely to make changes in your life because you have no one else to worry about. But that goes for any close people in your life and not just women (kids especially). If this is just an LTR and you feel like you are being a held back, that is a situation that I think you need to address why you have that feeling of being held back. If it is negatively impacting you, I wouldn't be afraid to end it. Some of my most productive times in my life financially and socially (on a professional level) have come after my adult breakups from marriage and long-term LTRs.
I want to balance both in a way.
I know successful guys from my network that are able to do this and make **** ton of money. It's hard and demanding. Especially if you have kids which I don't.
I don't want to destroy my relationship because my allocated time on wealth is more, I'm looking for a balance. But having a balance means that the results you might get on spending 2 - 4 hours a day on something instead of 12 will be much different.
And here is where the work smart and not hard principle comes in, I suppose in this kind of situations. Balancing Life, Girlfriend, and getting to the point where you are able to sustain your hobbies, business and keeping your relationship in check.
It does not negatively impact me because I love the chick I'm with. It's more about how to allocate my time on wealth without making her feel like she is a piece of dirt that I only bang and set aside. Because this is what will happen if I spend 12 hours a day in the office.