How long have you felt this way? When I first read your post, I thought "is this person depressed, perhaps" ? Not clinically, but perhaps the weather is getting you down? Or maybe it is seasonal or temporary and you can shake it off by getting more sunlight? Or exercise? You say you have just moved; are you having a hard time adjusting ?
If you feel really down for more than a couple of weeks straight, you might want to consider talking it over with a health practitioner whom you trust. Depression has a way of sneaking up on you, and before you know it, you forget what it felt like to feel good, and crappy becomes the "new normal". The solution for mild depression doesn't have to be drastic: it may be as simple as more exercise, stress reduction techniques, a slight change in diet to include certain minerals.. Or it could be a thyroid or other medical problem, or a vitamin deficiency, with depression as a symptom.
Better to get it checked out, and nip it in the bud to avoid more serious problems. In the meantime, try to relax and don't be so hard on yourself! Your vegetarianism probably has a much more positive impact on those around you than you realize!
And pets are a great way to reduce stress! Think of it as an exchange of services: you provide love, room and board, sanitation and security services, and your cat puts holes in your mosquito screening, wakes you up in the morning for his/her breakfast, and sheds copiously! And I never met a cat who did not do exactly what he/she wanted, given the freedom to do so. So if they rub up against you, expecting to be petted, trust me, that's exactly what they want you to do! In their minds, we exist for their entertainment, not the other way around!