I think I might be falling for a 30 yr old

Ok so I'm 19 and I have bf which I've known for 4 years and we finally made it officially this September. He's a great guy... But then there's this 30 year old guy at my job who has been in a relationship for 5 years... They're going through problems so he comes to me for advice. He says he feels comfortable speaking to me because I am very mature... He's so respectful and sweet.... I think we're falling for eachother. WHAT DO I DO?!