Disability forced me to see how work is far more to your psychology than just a means of survival or wage slavery. It plays a major role in giving life purpose. For instance, many people without the experience would say that my life, being stuck in bed most of the time would be great. The thing is, other than the pain, without a sense of purpose that a job creates, it is challenging to find and maintain an equivalent sense of purpose on your own. I have to take deep dives into hobbies and subjects to achieve a similar sense of purpose and satisfying accomplishment. I don't have the means or physical ability to take classes, and I have no social network to speak of at this point.
You have taken a hit to your sense of self and purpose in life. You're willing and capable of making decisions that are logical over the emotionally easier path of ignoring the logical in favor of the brain chemically addictive decision that has a poor long term benefit for you.
It will take time to find your place elsewhere and develop a sense of fulfilling purpose, but you've done this many times before in your life.
Everything is ultimately brain chemistry. Relationships of all kinds can be greatly oversimplified as addictions. It is okay to admit your addictions. It is the first step in recovery, even if those addictions are platonic and employment related. Like all breakups, this too will pass with time. Give yourself the opportunity to heal emotionally too, and recognize your needs for purpose by filling the interm with a fulfilling personal interest like hobbies or reading to bridge the gap.