My dds are 16 months apart, dd1 - 34mns, dd2 18mns, and I have felt like you at times - almost trapped if that makes sense. It does get better - it is just they are so dependent on you at this age that I think you feel the demands the most especially as they are both still depending on you so much - I found 15/16mns was better as they started to play together a little bit.
Also at 2.5 your older child can go to playgroup - leaving you a few hours a week just with ds1.
Toddler mornings are also worth a try, as there are lots of different toys than at home, and your children will probably play with other children - leaving you time for a coffee!
The endless nappy changing also will end - my dd1 is now potty trained - so a trip to the loo is so much easier than doing the nappy.
Mealtimes get easier too - as they now eat the same meal - just cut up more for dd2 - so you are not having to prepare different things for both of them.
I work 3 days and can honestly say this has been great for me, as I have some time where I am not in the 'childcare' routine.
Housework does not go away - can you do a bit at night - or does dp get home before bedtime - then one of you could watch the kids and the other do some housework - leaving you the evening together ?
HTH