The advice of taking a break from porn is both difficult and extremely helpful (speaking from experience).

Talk with your partner. You don't have to tell her you're addicted to porn, just that you're nervous and ask her to take things slow, to understand, and whatever else you think you need. Personally, I've taken things slow after a talk, had lots of foreplay, then performed just fine.

Something that's also fun and productive is to agree on no sex expected, but foreplay as much as you want. It often (but not always) turns in to sex and is very fun.