I'm too tired to comment on too much of this, but there seems a chicken and egg problem. My partner and I disagree about this, but I'm inclined toward it being easier to have sex and then reduce masturbation rather than try her way to not masturbate and then have sex. That seems especially true if we can have less heated sex. She seems to connect her view with a feeling there's a lack of interest in her. I don't see a connection to masturbation and if anything that becomes another layer of chicken and egg. Our differences might reflect how we see the palatability of more open relating to the extent that masturbation might be seen by some as infidelity. I'm curious what others think about said chicken and egg problem. I could be entirely wrong given that we've both struggled to not orgasm for most of our relationship. She tends not to between having sex, while I tend to give up, mostly sooner than later. Cuddling and bonding doesn't seem to tide me over and we're not around each other consistently enough.
Either way, things seems to become problematic when one partner wants more sex than the other. I've been the less interested partner too, though primarily because I'm too tired at night and there's rarely time in the morning.