So sometimes you may be in the situation where you need to do something you love in a bad situation. Divorces cause this many times. The work you love but the love behind the work is lacking. If you have a passion, doing this work with love behind it is wonderful. It elevates the work. But if its painful, it can diminish the work. Anger is generally not a great work driver nor is sadness.
So your options are to produce something subpar or to do your best. The choice and the work is very hard but the satisfaction knowing you did the right thing is paramount. Do not create regret. Also, the work may not be the best you have but it needs to the best you can do in that situation.
Do not create pain for yourself. Pay the price. Do what is right and help yourself move forward. Do not listen to the negative things people will say. Pursue paths and take actions you can live with.
And love yourself a little more when all is done. You did something nice for someone who may not deserve it in your mind but if it helps heal a hurt why not?
Be kind. Live, laugh, love.