When we make statements in natural language there are ambiguities and layers of meaning in even simple statements, but translating them into formal logic removes those.
In this case the original statement tells us that she is a single parent and that she needs all the help she can get (the AND statement from the book). It also seemingly implies that if one is a single parent, then one needs all the help you can get (your IMPLIES statement). However, in terms of logic, the AND statement is much stronger --knowing that both the AND version and the IMPLIES version are true tells us exactly the same information about this person as just the AND version alone.
To elaborate: If you have IF A THEN B you don't necessarily have A or B, you just have a guarantee that in the case you have A you also have B. So knowing that you do have A AND B is a lot more info than knowing IF A THEN B, because if you have A AND B, you always also have IF A THEN B. In fact if you even just have B, then you still will always have IF A THEN B.
The reason this is counter-intuitive is that in natural language, when we say "If A then B" we're usually not talking about one A and B, but a whole set of A's and B's --for instance, all single parents --which does in fact convey additional information. You can't express that in basic propositional logic --you would need predicates and quantifiers in order to do so.