It isn't true that God promises us He will never give us more than we can handle. Many, many Christians face circumstances that overwhelm and defeat them. Someone who teaches this isn't paying close attention to what the Bible actually teaches. God promises He will never present us with temptations to sin that are more than we can resist; and unfortunately, many people have interpreted that to mean "God won't give us more than we can handle." There's a HUGE difference! We may be certain that every temptation to do wrong will be accompanied by a way for us to resist that temptation, and that's a wonderful promise from God. But we will indeed face situations that are too much for us to handle, and that doesn't mean we've messed up our faith somehow, or that God doesn't love us. The nature of this fallen world guarantees that bad things will also happen to Christians and non-Christians alike, and some of those bad things will be more than we can handle ourselves. That's why God tells us we need each other, and why He tells us we need to be in a close and intimate relationship with Him through His Word and through prayer.
More to follow...