OK, so you state that you are "snorting your Ritalin, you don't want to stop drinking? and you want to stop? and you are unable to get past 2 days with no alcohol and you are blaming your parents for not understanding you, but you don't want them to know you are seeking help.
this is a bit of a confusing tangled mess....since you are only 24?, are you still covered under your parents health insurance?...this may make a difference in the type of treatment you are able to afford if you choose to actually de-tox.
please believe me when I tell you that addressing this now rather than later will only help you sort out and improve your life...please don't wait.
your bruising is actually bleeding under the skin and may spread...and as someone else pointed out here, heavy drinking thins your blood and makes you more susceptible to easy bruisng/black/blue marks.
a cream that contains vitamin K might help???