I have a 15 month old at home and really enjoyed these answers for myself as well :) We sound like we are in exact same situations and I too feel like I am forever trying to work on a to-do list that only grows....
I would echo some other answers and the things I try to remind myself daily...
1) A wise person once told me "this too shall pass." This has been my mantra! I remember always that certain phases of life with a little one will be more challenging in different ways and it just so happens with a child this age - accomplishing much of anything can be really difficult! Just remember that there are stages more difficult than others in our lives and when the kids can occupy themselves with a video game/movie or something - you can get some of those bigger projects done more easily.
2) I don't know what your income is like but if you are both working, perhaps you can fit some help into your budget. We recently decided it was worth it to pay a cleaning service to come every 2 weeks just to do kitchen and bathrooms. This helps tremendously because I can manage the small and regular things (dishes, vacuuming, etc.) but the deeper cleaning things are just too time consuming and spending that precious time with your family in the evenings on deep cleaning feels wrong! Same goes for paying a neighborhood kid to mow your lawn or other such tasks? It may seem expensive, but if you can afford it then your time may be worth a lot of money and piece of mind!
3) Please remember to take care of yourself. You cannot be a good wife/mom if you are not taking care of yourself as a person. My husband and I are realizing this and recently committed to a regular date night, every week. One week will be a stay-at-home date night (movies and pizza after the LO is in bed?) and the alternate weeks will be an ACTUAL date :) Also, time for yourself is important and I've found I have to actually MAKE myself put this in my schedule. If its a regularly scheduled thing, I find I will follow through (every Wednesday evening for example - coffee with a friend, a walk, etc.)
Good luck....this too shall pass!