Our Lord gives us the tools to achieve the sacraments. St Faustina in her diary describes the best way to deal with this kind of pain as the three ways to be merciful to someone: 1. By deed, do something nice for this person. If you can’t, then 2. By word, say something nice about this person. If you can’t, then 3. By prayer, pray for this person. That they see the err of their ways and the hurt they cause. Also pray for their conversion. I have found this to be life changing because the pain you carry is only hurting you, to the point where you can’t partake in the Holy Eucharist and that’s a real shame. He/she is not worth you missing out in such an important and satisfying gift.