It's an impossible question to quantify. All Colleges have pretty much the same provision for pastoral care, Chaplains, Tutors, College Nurses, access to free phone services etc. Everyone, UG, PG and staff also have access to an excellent University Counselling Service, and the various SUs.
There are multiple layers of pastoral support in all sorts of different directions (academic, health, mental health, financial, disabilities etc). The question that is impossible to accurately predict, is what is your issue and do you 'fit' with the resources available. But frankly, the resources are so extensive that it is hard to see how anyone can't find help if they look hard enough.