Your friend does not know Scripture or our ELOHIM! Tell your well-meaning friend that contrary to their guidance about your ills, it is actually more likely that if they, themselves are not suffering or have not suffered some affliction it is THEY who are probably not on God’s path! Ouch!
Scripture indeed tells us, in no uncertain terms, that we must suffer, and that our suffering helps build our characters and prepares us better for the eternal life we seek!
Yeshua said: "I have spoken these things to you that in me there may be to you peace. In the world will be affliction to you, but take courage, I have conquered the world." (John 16:33. AENT)
Let's see what scripture actually says:
Paul, James, Peter and Timothy wrote in the many letters of the Epistles, there is a valued purpose in our earthly suffering!
8. Be mindful of Y’shua the Mashiyach, that he arose from the dead; who was of the seed of Dawid, according to my proclamation, 9. in which I suffer evils to bonds [i.e., ‘chains’] as if an evil-doer: but the Word of Elohim is not in bonds. 10. Therefore I endure everything for the elect’s sake; that they also may obtain life in Y’shua the Mashiyach with eternal glory. 11. Faithful is the saying, For if we will have died with him we will also live with him; 12. and, if we will have suffered, we will also reign with him. But if we will have rejected him, he will reject us." (2 Tim 2:8-12. AENT)
2. Let it be all joy to you, my Brothers, when you enter into many and various trials. 3. For you know that the trial of (your) faith, makes you possess patience. 4. And let patience have its perfect work so that you may be complete and perfect and may lack nothing. (James 1:2-4. AENT)
3. And not only so, but we also rejoice in afflictions because we know that affliction perfects in us patience; 4. and patience, experience; and experience, hope: 5. And hope makes us not ashamed because the love of Elohim is diffused in our hearts by the Ruach haKodesh who is given to us. (Romans 5:3-5. AENT)
7. And, that I might not be uplifted by the excellence of the revelations, there was given also to me a thorn in my flesh, the Messenger of Satan, to attack me that I might not be uplifted. 8. Respecting this, three times I begged my Master (Y’shua), that it might depart from me. 9. And he said to me, "My grace is sufficient for you; for my power is perfected in weakness." Gladly, therefore, will I glory in my infirmities, that the power of the Mashiyach may rest upon me. 10. Therefore I have pleasure in infirmities, in reproach, in afflictions, in persecutions, in distresses, which are for the Mashiyach’s sake: for when I am weak, then am I strong. (2 Cor 12:7-10. AENT)
3. And endure evils as a good soldier of Y’shua the Mashiyach. (2 Tim 2:3. AENT)
12 And likewise all who choose to live in the Fear of Elohim, in Y’shua the Mashiyach, will be persecuted. (2 Tim 3:12. AENT)
12. My beloved, be not dismayed at the trials that befall you as if some strange thing had come upon you; for these things are for your probation [i.e,. the act of testing]. 13. But rejoice that you participate in the sufferings of the Mashiyach that so you may also rejoice and exult at the revelation of his glory. (1 Peter 4:12-13. AENT)
So you see our sufferings while in our mortal bodies on earth, including the many ills we face, is expected to mold us into a form of "perfection" to be worthy of eternal life! Seeing our ills as "sharing in the suffering of the Messiah" (1 Peter 4:13), may be very hard to do and hard to take, but when we realize that these are tests of our faith to help build us for our ultimate presence with Him, we can, as scripture indicates "take joy in our trials, for they are for the Messiah’s sake." (2 Cor 12:10).
And look at it this way, if your friend has no ills, or has not suffered, then what good are they to others? How can they empathize? How can they teach others how to bear pain? How can they understand and share their experience and lead others to the gift of eternal life? (2 Timothy 2:10). How can they say their faith has been tested? (1 Peter 4:12).
No, your suffering, your ills, bear witness that you are on God’s path! Rejoice! (1 Peter 4:13).
And remember: Loving YHWH your God, paying attention to what he says and clinging to him - for that is the purpose of your life! (Deuteronomy 30:20. CJB)
Of course we must all go through trials – endure ills and suffering for probation. But these ills do not mean we are "not on God’s path"! Rather, they are brought to us usually through no fault of our own by "the world" because it is fallen. But you very well might not be on God’s path! You can’t call it a "test of faith" if your ill or pain is self-induced – drug use, alcohol abuse, sexual misconduct, obesity through over eating or laziness, etc.
Scripture also amply speaks about our own responsibility to eat right and to take care of ourselves. Leviticus 11 addresses what animals may be eaten. 1 Corinthians 6:15-19 talks about sexual misconduct, how it defiles the body. And: "Be sober and guarded because haSatan, like a lion, roars and goes about and seeks whom he may devour." (1 Peter 5:8, AENT). (Read that verse carefully!) No, if you are suffering an ill not of your own doing, take comfort to know that it is to build you up for the Kingdom. You may not understand just why, or how, but your role is to trust and not lose your faith.
Remember: For, though He was executed on a stake in weakness, yet He lives with the power of Elohim. We also are weak with him; yet we are alive with him, by that power of Elohim which is among you. Examine yourselves, whether you stand in the faith: prove yourselves. Don’t you acknowledge that Y’shua the Mashiyach is in you? And if (he is) not, you are lawbreakers. (2 Corinthians 13:4-5. AENT)