As indicated in my comment, it is possible to "overburden" yourself, and there are different degrees of effects from overburdening depending on severity and timescales. Any overburden with enough time can lead to burnout (Carter, 2013). Other names for burnout include "mental breakdown" or "nervous exhaustion/breakdown". Another form of burnout, but essentially the same thing is Compassion Fatigue (Carter, 2014)
Definition of Burnout
Burnout is a state of chronic stress that has led to extreme physical and emotional exhaustion, which in turn can lead to cynicism, detachment, and feelings of ineffectiveness and lack of accomplishment.
Carter (2013) has given a good rundown of the problem, but I would suggest subsituting the section header Signs of Ineffectiveness and Lack of Accomplishment with Feelings of Ineffectiveness and Lack of Accomplishment can lead to...
Prevention/Remedy for Burnout
This can be a huge subject, but to narrow it down in a nutshell, as burnout is caused by chronic stress, the only way to prevent it or remedy it is to do whatever relieves stress for you and incorporate it into your day, every day. Burning the candle at both ends along with the midnight oil every day is going to lead to burnout.
Carter, S. B. (2013). The Tell Tale Signs of Burnout ... Do You Have Them? PsychologyToday [Online]
Retrieved from: https://www.psychologytoday.com/gb/blog/high-octane-women/201311/the-tell-tale-signs-burnout-do-you-have-them
Carter, S. B. (2014). Are You Suffering from Compassion Fatigue?:
What to do when showing compassion feels like a burden PsychologyToday [Online]
Retrieved from https://www.psychologytoday.com/gb/blog/high-octane-women/201407/are-you-suffering-compassion-fatigue