In my area there is a woman-owned firm producing a specialty beef that is extremely low fat, low calorie and 100 percent organic with no antibiotics, etc. This beef is expensive but worth it for taste and health benefits. This product can run approximately one-half the calories of even the leanest cuts of run-of-the-mill beef. So maybe there is a similar specialty beef in your area?
Beef really is not the health villain it is often thought of as being. I used to be a vegetarian but for various reasons decided to go carnivore a few years ago. Beef is the main reason I did that. It is an excellent (one of the few) source of heme iron, which is only found in red meat. However, you don't need a lot of beef to receive sufficient amounts of this, so the idea of using beef as a kind of seasoning as Suzanne said is a good one.
Pork is generally a very lean meat these days, similar to turkey and chicken but offering different nutritional benefits.
IMO, there's no reason not to eat pork or beef if you like it and eating a variety of protein sources can offer health bonuses you won't get if you just stick to chicken. Moderation is the key to any healthy weight loss diet, IMO!