The context is a typical conversation. You've settled for a course of action and expressed yourself accordingly. Then you get from someone a warning of sorts about potential risks or consequences stemming from your choice, along the lines of: "you are aware that this will..., are you sure that...". So it's either a warning or the person reacting to something and requiring acknowledgment of the concern. Then you may want to retort that you understand but that you're still right on course so to speak. The intent is to showcase the choice and your determination, maybe even your stubborn nature; it may be spirited or even defiant, yet not impolite nor confrontational; it is not about a burden, nor the surrendering to an ill fate or design; it has purpose. It respects, but does not concern itself with, the opinion of others. 1
Collins dictionaries provides a translation of the French verb assumer(that verb in that language bearing the meaning I'm looking for) into an intransitive form: "to live with it". My first thought is to live with an illness, to live on despite a negative situation/choice, etc. It feels like a chore and further seems to cater to the warning rather than the choice. In BrE it seems it can indeed mean to endure the effects; other connotations are negative. As for "bring it on!", it just shows the other end of the spectrum: excitement, fearlessness in the face of the challenge, which connects here, but it also seems more fitting when there is a risk of bodily harm, such as with (contact)sports.
Is there a middle ground between "I'll live with it" and "Bring it on!"? What expression could be used as a reply in the context of that conversation and which better matches the tone and meaning provided(take upon oneself willingly "all" etc.)?
1. In so many words, it is the "J'assume!" in French(see translation on Collins). Simply put, it seems often in speech to assume with no object is to suppose, whereas in French the (much)more usual meaning for the verb assumer here is to take upon oneself, as in "j'assume une tâche, un risque, les consequences de mes actes etc.". So much so an object may not even be required in casual speech: I assume(all). The word supposition is the common ground and usually means the same thing in both languages. But even if the verb to assume can also mean to take on etc. in English, it doesn't settle this as in the context of the aforementioned dialog, answering "I assume" with no object often triggers the expectation for details about what you're assuming, hinting that this isn't idiomatic at all imho.