Should I race!?!?

Advice (or support) is needed...I am debating if I should participate in a scheduled 70.3 next weekend. I haven't been injured, but life has gotten in the way of my training and I haven't been able to train like I should (and my eating habits completely stink). I did the same HIM 2 years ago and did IMWI last September. I know I can do the distance, but not sure if I can do it now and finish with a smile on my face. Since last September I was a part time care taker (and working full time) for my sister in law/great friend who was battling Leukemia (she lost her battle 3 months ago at the age of 31 and it's been a rocky road). This last week I had to officially sign my mother up with hospice as she is terminally ill. So, lots of stuff going on personally.

Long story short, my training has been half assed over the last couple months, I weigh about 10-15 pounds more than I did during any of my other two races. I know I can do the running part (as I just ran 17 miles this past weekend--in the middle of training for a marathon as well). But the thought of all of them put together and being able to finish in a reasonable time is freaking me out--should I push it? Drop out? Or go out and have fun with it? I do have one other friend doing it with me --so I feel I shouldn't let him down.

Any advice is greatly appreciated---thanks!!!