I think you may be able to make it in Orange County, which is a much prettier area with better weather and closer to the beach compared to the Inland Empire. Specifically south Orange County would be a great area to live. It is a collection of several suburban cities that are really nice. They are covered in trees, master planned, extremely safe (Mission Viejo, Lake Forest, Irvine in top 10 safety rankings in the country), and have award winning schools. If your looking for that great California weather, then the Inland Empire isn't amazing. In the summer, the temperature tops 90 degrees everyday and gets into the 100's during a heat wave. In the winter, because it is so inland, the temperature is colder than the coastal areas which are regulated by the effects of the ocean.
As far as individual cities, I recommend Mission Viejo, Laguna Hills, Rancho Santa Margarita, Laguna Niguel, and Lake Forest. I think you should be able to buy a single family home for about $450-550k and keep a similar mortgage payment. The houses are more expensive here, so you are looking at 1,300 square feet, while in the Inland Empire you could probably get 2,500 square feet or more, but I think where you are living is very important.
Here are some sample listings: (let me know if these don't work)
22591 Via Loyola, Mission Viejo, CA | California Real Estate | Listing Information
The above home is set in a clean neighborhood off Los Alisos Blvd. The home is only one mile from Lake Mission Viejo and is close to an open space park. It has been nicely renovated inside. Attends Barcelona Hills Elementary, Newhart Middle School, Capistrano Valley High in Capistrano Unified School District.
22571 Via Loyola, Mission Viejo, CA | California Real Estate | Listing Information
The above home is a little older than the other, but it larger. Needs a little work, same schools.
28051 Blandings, Mission Viejo, CA | California Real Estate | Listing Information
Charming home in a nice neighborhood called California Colony. It is close to walking trails and Lake MV and shopping centers. Saddleback Valley Unified School District.
21566 Cabrosa, Mission Viejo, CA | California Real Estate | Listing Information
This bank owned home is ready to be sold. Close a city park and walking distance to shopping and schools.
27041 El Retiro, Mission Viejo, CA | California Real Estate | Listing Information
This one is in my opinion a really great house. It is clean inside and well kept inside and out. The schools are great and a community park and tennis complex is in the middle of the neighborhood.
Those are just a few examples, but there are many more single family homes and condos in that 450-550k price range if you can afford this.
As far as working at a hospital: Saddleback Memorial Medical Center, Mission Hospital, Saddleback Memorial Medical Center at San Clemente, Irvine Medical Center, and Kaiser Permanente Hospital of Irvine are all 30 minutes or under from south county cities like Mission Viejo. We are located halfway between San Diego and Los Angeles, are fifteen minutes to the beaches of Dana Point or twenty minutes to the beaches of San Clemente. We have a beautiful lake at our city center for swimming and boating. I will include pictures of the area below.
Lake Mission Viejo (with snow on Saddleback Mountain- very rare, what makes the shot great)
Montanoso Drive
The trees lining the main north to south street in the city, Marguerite Parkway.
Los Alisos Parkway and on the left, a open space park
From a hilltop looking down into the Saddleback Valley behind the homes.
Award winning Mission Viejo Library
Twenty minutes to the beaches of San Clemente
Well that will hopefully give you an idea of the area. You should expand your horizons to more areas of So Cal. Good luck in finding a place to call home. Sorry for the length.