There is no need for you to worry over this. Allah has categorically stated in the Qur'an that if anyone is sick or travelling, then let them fast other days'. And, as for those who cannot make up due to an incurable affliction, they should give fidyah which entails feeding a poor person for each day. If, however, a person cannot pay it due to lack of resources, they can pay later; if they couldn't do so, they are excused.
Allah reminds us in the Qur'an on numerous occasions that His laws are not intended to create pain or make us suffer unnecessarily; rather they are intended to bring ease and comfort.