What does my girlfriend mean by this ?!?!?!?

My gf & I are together for 1.5 years, we had a break up in september but we patched up in november again & everything was fine. Recently we were having some chit chat about one of our friends who checks out girls but doesn't commit to any relationship. So I asked my gf what'll she do if she gets a check out proposal from him.....she said she is committed to me. Then I asked her what if she was single, she said that the guy is very tall & she'll scold him for his bad choice :P. But she says theres no harm in temporary relationships just to check out whereas I only believe in commitment. Is my gf committed to me ? Or am I being checked out too ?