
The key difference lies in two elements. The first is whether you need to justify and make excuses for the behavior you are supporting. There is no need to excuse positive behaviors. The second difference is associated with yourself. Enabling means ignoring your own needs, desires, and emotions. Often, it means that you allow the person with addiction to do something at your expense or at the expense of your family.
A mental health professional and a support group for yourself can help you differentiate between the two further. Giving your partner the support they need can be much easier if you also take care of yourself.
References
Kelly, S. M., O'Grady, K. E., Schwartz, R. P., Peterson, J. A., Wilson, M. E., & Brown, B. S. (2010). The relationship of social support to treatment entry and engagement: The Community Assessment Inventory. Substance abuse, 31(1), 43-52.. https://doi.org/10.1080/08897070903442640