please need advice: cat/urinary (and grief) problem

Hi, Please help. My cat has developed a urinary problem and I need some advice. I have posted here once before (Nov.'08) regarding my same boy, his name is Bernie. Being unfamiliar with how these forums work. I checked for a week, didn't get a reply and thought I wasn't getting one. Now that I'm coming back to ask for help again. I see that I did get an answer. So, thanks Orion if you're still out there. I found your answer helpful today.
Over the last few days I have been feeling that Bernie was not quite himself. Last night I noticed that he was showing signs of urinary infection again, squatting where he shouldn't without much quantity left behind. This has not happened for Eleven months now from looking at my last posting. Note: Six months ago to the date, our beloved dog & his best friend passed away suddenly (heart attack, not sick prior). Besides for myself and my husband, Bernie took this very, very hard. In all my life I have never seen a cat grieve like he did. Going to where our dog passed, laying there and crying (a sound that was heartbreaking), and Bernie is an indoor outdoor cat - explain more later on that - he would go to our dogs memorial site, lay there and cry, becoming agitated if I would try to remove anything from that area such as placed flowers that have died. Bernie is very sweet & sensitive, sleeps with me at night tucked up close to me between my body and my arm. I can tell that he is still sad and feels the loss of our dog even though he will now leave those areas I mentioned.
A few nights ago he didn't sleep next to me. Became very insistant with crying to go outside. He is allowed outside only in the morning for a few hours, then back inside for some time, and then is let back out in the afternoon until dinner time and not allowed out after dark or if bad weather (chilly or rainy)- also in all night. He stays close to the house, I check on him frequently, he just likes to sun himself. Our weather here is still very hot (80's-90's) and dry. He does have water available to him at all times. Last night he came inside, ate dinner, had his dessert (some dried catnip which he loves!) and after he ate is when I noticed him do the squat,then wanted to go back outside which he knows the routine well...is not allowed. I gave him a dose of cantheras pellets made into a powder last night. This morning he was not allowed to go outside so I could watch him all day. He was frequently trying to pass urine this morning but not a lot of quantity each time. I did give him a little more cantharis, set up a box for him only to use that has a small white trash baggie in it so I can see color and quantity, then using a syringe gave him a good amount of water. As of this morning he was trying to squat every couple of minutes and going about the size just larger than a dime, yellow in color. Once I gave him the syringe of water I can see that he is definitely passing some more urine, 4x more than earlier, he has had a cranberry capsule a couple hours ago now, the urine looks just a little more colorful - deeper yellow. After reading the reply to post from last year that came in Dec'08. I did not give the vitamin C this time with the cranberry. Keeping a very close eye on him, not going anywhere. If anyone has any suggestions or advice for me please answer. Wondering if there is anything else I can be doing for him at this point besides what I have done. Thank you all for reading this, and in advance for any replies! Hugs!