Initially intended as a long comment, but:
In this case we cannot tell you what to do, just provide minimal guidance.
If you're the primary lessee, you're on the hook for everything involving that unit.
If the mom decides not to pay rent, you're on the hook.
If the mom decides not to pay utilities and the contract requires running water and power during occupation, you're on the hook. If she brings in a pet or damages the unit, you're on the hook. If anything comes up during inspection on move-out, you're on the hook. And if they evict her, you got it, they really evicted you, and that goes on your record.
If you're co-lessee with the mom, you're still on the hook but so is she. In this case the relationship you want to maintain with the mom will influence your decisions, and the potential for power plays exists.
A strategy here would be to look at your lease, look at severance. Common terms are you either (a) find a tenant for the unit to sub-lease, (b) pay 2-3mo rent, potentially forfeit your deposit and sever the lease, or (c) pay the remainder of the value of the lease and sever the lease. Of course in "a" you could talk to the mother about sub-leasing (which the landlord must generally agree to in writing), but in "b" or "c" she would have to move elsewhere or become the tenant, meaning she pays a new deposit and first/last month's rent or what have you.
Without more information about your lease contract, and providing that IANAL, this is some very obvious guidance and I can do no more for you.