well honestly with access you could just buy a cheap 9 dollar disk drive, but without you would have to get her to open something and download a key logger...this sounds like your relationship is going down hill
ERMM... Some one is paranoid and intrusive
But If you realy want to be a sucky BF then fair enough
Google it and their are many peice's of software for this kind of thing ( Mostly Paid )
And they are stealth too so like they run in the background hidden so the person using it doesnt know.
I don't mean to be a SGT. Buzzkill but I don't think this is allowed.
What's the main reason why you want to do that?
Do you suspect her of cheating? Porn?
I could give advice on that but I don't know anything about keylogging.
You can't remotely access her computer and it would be illegal to try. If anything download a free trial keylogger from a reputable source and then run it on your own comp then have her come to your house and sign into her email. Then you will have her password. This is not illegal.
However I know nothing of macs and installing programs so I'm not sure if this option even applies to you. Tbh you are better off just confronting your gf or being insecure and reading her phone messages...