When you are seriously sick, you can't just ignore it. You have to admit that you are weak, and you have to go to the doctor. If you don't, you won't be able to get the help you need. You will get weaker and weaker and you might never heal. But if you do get help, you can get on a path to recovery. The doctor can prescribe or recommend medication, therapy or other procedures that are necessary for you to become strong again.
So how about when we are spiritually weak? When you feel like your relationship with God isn't strong enough? When you feel guilt and shame because of sins that you have committed? When you want to strengthen your relationship with your spouse? When you have a desire to be better at reading the scriptures?
And if men come unto me I will show unto them their weakness. I give unto men weakness that they may be humble; and my grace is sufficient for all men that humble themselves before me; for if they humble themselves before me, and have faith in me, then will I make weak things become strong unto them. -Ether 12:27 (Book of Mormon)
When you are spiritually sick you have to do the same thing as when you are physically sick. You have to be humble and admit that you are weak. Then you have to go to Jesus Christ who has made it possible through his atonement for us all to repent and make changes in our lives. He will recommend or prescribe things that will help you to become stronger. His grace is sufficient to help you become strong! What you have to do is be humble, put your trust in him, and do what he says.
I am weak. I make mistakes every single day. And that is alright. It is okay to be weak. There are things that we all need to work on. The most important thing is that we turn to our Heavenly Father and Jesus Christ who will make us become strong.