Sometimes, people can feel an inappropriate responsibility for those around them. At times this is the cause of distancing: attempting to escape more emotional responsibility than any other adult should have for another adult (under average circumstances).
On occasion, the other adult in the relationship (partner, friend, family member) may come to expect more from you than is fair or reasonable, and this might mimic dynamics in our early attachment figures. Despite this, we might be processing their needs for obligations.
Maybe we learned that we're not allowed to say no. As a result, we may passively say 'yes' but then not follow through or emotionally check-out, or maybe we simply run away to avoid having to answer to the situation.
Do you recognise this in yourself or in someone that you are close to?
This is very symptomatic to an avoidant attachment style. One of the main points of work for avoidants is allowing others to express their need without imagining that just because needs have been expressed, it means we're automatically obligated to meet the need. Other people's needs are much less scary when we don't instantaneously feel locked into meeting them once we hear them.
Practice hearing the need and not jumping to do anything about it. Without running away, defending, or rushing to agree to it in order to get the experience over with. Try acknowledging what you have heard and communicate how you would like to sit with it for a while before deciding on anything. Then, continue to be connected to that person.
If you would like to hear more about attachment styles, let me know in the comments or drop me an email and I will deliver.