I agree with the previous posters.  Apple is a control freak so they do have the system pretty well protected.  Having said that, Macs are not 100% shielded from viruses or malware.  About 6 months ago, a Mac friend received an E-Mail about his bank.  He wasn't paying attention and thought it was legit as he had an account with the bank.  Ayep, it installed a bunch of software and messed up his Mac.  He couldn't use Safari or Firefox to access the web as it was redirecting him constantly and displaying popups.  I can't remember what the other software it installed.  He ended up calling Apple's tech support and they were able to remote into the computer and clean up the virus.  I am not a fan of anti-virus software because they greatly slow down the computer and the current anti-virus software wants to install so much additional stuff on your computer, slowing it down even more.  The greatest defense is being smart.  Don't open up every E-Mail you receive.  Tread cautiously when you visit a new web site.  If you visit a site and something unexpected happens, don't be curious, shut down the web browser.  Many will display a "click here" to close.  Never use that.  Close the browser like you would close any program (be it Apple or Windows).  Worst case, hard reset the computer.  If you receive an E-Mail and can't tell if it is legit and you have an account with the business, don't click on anything in the E-Mail, call the business and confirm.  Please don't use any information in the E-Mail, including telephone numbers.  If you don't know the business' phone number, use a search engine.  Trust your gut.  Usually the trigger will be something unexpected.  When you notice it, error on the side of caution, close the program or E-Mail.  If not quite certain how, shut off the computer.  If you are still prone to getting malware or viruses, even on a Mac, you should get some protection.  True anti-virus software will have a slight impact on your computer but that would be a small price for the protection.  At work this week, someone's computer had the cryptolock ransomware.  The headache of having to deal with viruses, malware, or ransonware is too frustration and time consuming.  Best of luck and be safe.

Definitely prefer a condomless experience.  Unfortunately trust is a problem initially so condom-only in the beginning.  I met up with a guy at a local hotel once.  We both required condoms.  We had a good time and spent more time together than either planned.  He started getting hot, I was out of condoms but he wanted me in him.  I had only the slightest temptation but told him we would have to save it for another day.  Though I am sure we both felt both were ok, it was just a risk I wasn't going to take.  Trust and testing.