If ‘resistance’ is a force that we exert – as in opposition, hostility or aversion to something or someone – then it’s worth remembering that it can take a lot of effort,
If one is unwilling to accept something, in the context of interpersonal relationship, then you could try asking what makes the resistance necessary, instead of simply pushing to overcome it.
Whoever is doing the resisting, you or somebody else, as you might have noticed, force tends to create a counter-effect; resisting creates resistance.
If it’s within you, you are really only fighting against yourself. If it involves two people, then both will be struggling on two fronts; to maintain their own position and to resist the other person. Tiring!
To break the cycle, it can be helpful to think of resistance as a facet of the relationship, not a peculiarity of the individual(s) concerned.