I haven’t yet read any of the answers, but will do so after posting.
It totally depends upon why you decided to become a vegetarian. I think a lot of people try vegetarianism because it tends to be a healthier diet.
I am one of those people that believe that it is not necessary (in this day and age) to kill and eat animals. I never disliked the taste or texture of meat, but for me, killing and eating animals is a very cruel way to live, in the absence of necessity. I try to live my life by doing the least amount of harm. But that’s just me. My way is not necessarily the best way or the right way, but it is the right way for me.
I have found other things, vegetarian things, that taste divine to me. Things that I would never have bothered to try, before I became a vegetarian. I guess I never really had cravings for meat after I gave it up, although some items still smell good to me and make me salivate, but I’m totally fine and content to enjoy the scent without having to jones for the actual food itself. It’s like the scent of pine, or a campfire, or an ocean breeze, something wonderful to smell, but it’s not something you eat.
Being a vegetarian is hard. Mostly because I have to do a lot of work and research, and I have to answer a lot of ignorant/instrusive inquisitive questions from people who don’t share or understand my way of life. But for me, the reason behind why I am a vegetarian makes it much easier to live this way, than it would be for someone who is just going veg to eat healthier.
You need to decide why you decided to become a vegetarian in the first place.
If it was simply to have a healthier diet, then go ahead and add the meat (which includes fish) back into your diet, just make sure you eat lean meats, fish that is not high in mercury levels, and food that is prepared in healthy ways, along with your fruits and veggies. Health-wise you’ll be fine.
If you are more like me and wish not to consume, or contribute to the death, of other living beings, then it’s going to be a lot harder for you, until you do a lot of soul searching. Cravings come and go. Find stuff that you like, not necessarily substitutes, but other vegetarian foods that you love, maybe stuff you’ve never tried before. You can also experiment with substitutes, there’s a lot of tasty fake meat products available today, that weren’t available 25 years ago, when I became a vegetarian.
If you need any suggestions let me know. If you decide not to be a vegetarian any more, don’t beat yourself up, most people fall off the bandwagon.