I quit a dream corporate job at 29 and spent two years traveling the world several years ago. I am still paying off credit card debt from my journeys and still haven't gone back to earning the same level of pay. But I wouldn't trade that experience for anything.
Can't tell you whether or not to go. I made the decision to leave at the spur of the moment in hindsight. Here's a few thoughts however.
1.) know what kind of traveller you are. Me? I can't do the whole stay in hostels, 20 buck a day routine. I need my privacy too much. Don't try to travel in a style that doesn't match your personality or there will be trouble.
2.) in many ways, it can often be cheaper to stay in one place longer than to do multiple places in the same time frame. I went to Brazil for 4 months. I was able to sublet an apartment for 4 months on the beach in Salvador for less than it would have cost me to get decent hotels and travel costs for a week in Rio, a week in São Paulo, a week in Salvador, a week in Brasilia, and a week Recifie. Factor in being able to cook at home than eating out, and it can make a huge difference in costs if you can have prolonged stays rather than seeing a different place every few days. Again, however, know your travel style.
3.) see if you can work remotely. I was fortunate in that I was able to find employment that we're cool with me working remotely on a random schedule (project based work helps, I.e. As long as the work is done to the right quality by a certain deadline, the boss doesn't give a fuck where you do it). I lucked out on being able to find stuff that worked for me, look around, there is more of that stuff than you think these days.
4.) make the things you leave behind make money for you while you are gone or at least be cost neutral. I sublet my apartment and basically rented my car to a friend with bad credit who couldn't get a car on her own.
5.) you can do some amazing travel in the United States. People always feel like they have to go to Uzbekistan for travel to be valid or rewarding. Certainly it is awesome to go far afield. I am writing this right now from a island off the coast of Panama. But the U.S. Has a ton of cool stuff that is as weird and wild as some of the most random shit I have experienced in far flung places. One of the best parts of my time being rootless was six weeks I spent in Los Angeles. New Orleans is a city you can spend weeks falling into. Coastal Oregon is amazing. Try yourself some Canada while you are at it.
Good luck. I hope you get to travel, but do it your way. If you let your gf pressure you into traveling in away you dislike or on a schedule you dislike, you will have a bad time. Have you two travelled before? Do you get along on the road? Nothing is worse than a mid travel breakup (been there, done that, middle of 2 month trip to Europe). Mismatched styles and expectations kill relationships.