Erica,
Your post is all too familiar. I was diagnosed with rectal cancer in Oct 2016 ( at age 29 with a 5 month old at home). Subsequently I had a total proctocolectomy Nov 29th with temporary ileostomy and j pouch creation. In February, I had the reversal and I am now 4 months post takedown. It has been the most awful experience of my life. I too had problems with the ileostomy, but it daily crosses my mind if it would be worthwhile to have a permanent ileostomy. I returned to work after 5 weeks and have been back to see the surgeon several times due to continued pain, fissures and internal hemorrhoids. I now have decided that it is futile to return because the last time I was there, I had another pouchoscopy and the skin was raw/irritated and fissure still present. The surgeons answer was this can take "years" to heal and sometimes heal and then reoccur. I wasn't told any of this before the surgery. Just that it would be back to "normal" life. Hahaha! What is that??? Botox sounded pointless because it would worsen incontinence and only relaxes the internal sphincter temporarily and then you would need continued injections to prevent fissure reoccurrence. I have used numerous creams. The ones that I have found the most helpful are calmoseptine and nitroglycerin ointment. I just tried the rectacare otc 5% lidocaine and it is amazing. I can actually fall asleep without having to go sit in a hot bath for a bit. Ps-- burns severely for a minute or so after application. I have learned to stay away from insoluble foods because they cause delayed healing of fissure and are incredibly painful. I lived on carbs for a while, but felt so horrible due to poor diet. I started taking 2 flinstone vitamins daily and a b 12 supplement and an activia. My BMs have decreased to about 12 a day (2-3) are at night. 
Eating earlier in the evening helps this, but is not usually possible. Dairy increases the number of stools. I find liquid stools are way less painful than even semiformed ones and I was prescribed linzess to keep stools liquid (I had to have a stricture dilated as well). Only taking half of the beads in the capsule daily does not increase the number of stools by much but really helps with the consistency and reduces straining. Could you have a stricture and this be a cause of you having to strain? Butt burn has been another severe issue. I have found that staying away from anything well seasoned, citrus or acid foods even chocolate and coffee have helped tremendously. Unfortunately, I eat nothing now that I enjoy. I completely understand how you are feeling. It is awful. I have always run... had a good day Monday and went for a run. Big mistake. Back to SEVERE pain. I pray that time will heal, but this is depressing and horrible. Hopefully something that I have tried will help you.