Is coveting your neighbor's vacation a sin?

I get you're not supposed to covet your neighbor's spouse or possessions but I admit I am very, very jealous of one of my coworkers vacation plans. I think my jealousy started hitting hard right around the time I started making Thanksgiving plans. I know living an hour or more from different relatives makes it difficult to get together on holidays. I planned on having Thanksgiving at my house because I had been hoping to have my mom there and with her health it'd have been too hard to bring her to someone else's house. That's not going to happen at all which makes it just hurt worse. DH's side has plans. Fine, I understand. My sister and niece were supposed to come. Niece wants to go to father's; sister doesn't want to make the drive by herself. So, Thanksgiving will be DH, me and the kids. I'm fine with that, really. Okay, not really but I don't have much choice. Growing up, my mom always insisted I be there for Thanksgiving; it was the family holiday. Since we flew on employee passes, we usually spent Christmas flying or at airports but Thanksgiving was dinner at home with turkey, baked apples, and whatever friends didn't have somewhere to go. My mom's physically still here but mentally she is slipping away faster and faster. This just seemed like a time when I really needed family around. I will still have my family of course, DH and the kids, but I wish there'd be more of us. The nursing home advised us strongly not to take my mom out for the holiday because of the frequent transitions she's had to have over the past 2 months, her paranoia, and her fantasies. So, that sets the stage for my jealous coveting.

A coworker is going on a cruise at Christmas with about 20 people in her family. I know some think I'm crazy but I think that would be the ideal trip - cruises have so much to do that people could do what they wanted and catch up throughout the trip (I'm not crazy enough to think that we should all be doing the same thing all the time). I treasure the memories I have of traveling with my family. I am so glad that my son has those memories of my mother; it hurts my heart that my daughter won't have those memories. I know it'll never happen but that doesn't stop me from wishing.