Life doesn't have meaning. Only you have meaning. You put meaning into all your experiences, relationships and things you do. With that said I understand why people prioritize their work and other commitments. They are what give you a sense of purpose, however I have to emphasize the fact that you can do much more if you take care of yourself first. It's one less thing the rest of the world will have to worry about and more importantly you will have an easier time fulfilling your other commitments.
Your life will be most effective and require the least amount of effort to sustain if you address the following 4 sections in order.
I've been going on and on about developing efficient movement patterns. This will require both physical and behavioral changes. The positions you assume at work, or while going about your life will impact the way you move in the gym. The environment also effects movement efficiency. So you have to get to the root of movement issues and take the time to reverse engineer patterns that have been hardwired over years of conditioning. Biomechanical pathologies are treatable at any time or stage of development. But it takes time, consciousness, and a ton of practice. It starts with understanding the movement principles and then practicing and applying them to every facet of your life. So if you already have an injury its not too late to make corrections and if you haven't yet developed an injury you will save yourself from shoulder, back and knee pain.