God is a loving and merciful God. He knows your frame; He remembers that you're but dust and He knows how much you can stand. (Psa.103:8-14) Even of our service for Him, Jesus said, "My yoke is easy, and My burden is light! Come unto Me, and I will give you rest!" (Mat.11:28-30)
So if the yoke gets too hard and the burden too heavy, it's not His yoke nor His burden, but our own or someone else's which we've unwisely undertaken or permitted to be placed upon us beyond the Lord's knowledge of our strength and abilities!--Or maybe you're trying to carry too much and pull too hard, instead of letting God do it through you by His power, His Love, His grace and His strength!
The Devil tries to come along and tempt you to quit, "Oh, that's too hard, that's too much, that's too heavy!"--But Jesus said it is not!
The Lord's yoke is not too hard and His burden is not too heavy. So if you take it from the Lord and do His Will it's not going to be too hard or too heavy. He Himself will never suffer us to be tempted above that which we are able! He's promised to always give us some way of escape! (1Cor.10:13)