Hi your story seem very similar to my own

 My mom managed 2 rounds of Chemo but it made her so tired to the point she was spending most of her days in bed unable to mobilse herself.

She has had so many bouts of infection from chest and utis which literally knock her for 6 and she ends up in hospital. She has had  ivud twice while I  hospital. 

We have just found out that the cancer has spread further and she shouldn't continue with treatment as it is not working. She has been off Chemo now for a about a month and she is like a new woman, she's still not fully mobile but she is out of bed and not sleeping all day which is amazing, we are starting g to feel like she can actually start to enjoy her life again and make some plans and tick off a few things on her bucket list

Time wise we don't know how long she has but I'm so glad to have my mom not suffering the effects of Chemo anymore. 

My mom takes oramorph but is also on a morphine patch with is keeping her on a good level of pain relief then uses the oral one for breakthrough pain and to help when her breathing is bad. She was very uneasy about taking too much morphine and was suffering unnecessarily but it's there to help, if you need it you need it, so I wouldn't worry about the increase. We have just been told to record every dose so they can see how much is needed over time so they can adjust the patch dose.

What we have found though is every professional my mom speaks to gives  slightly different advise, so I think it's a case of figuring out what works best for your mom. The most important thing is being comfortable and In a place where you can enjoy what time you have left, so if something isn't working change it. St Giles and Macmillan are fab and the community nurses can advise too. 

I hope this helps xx