This is my first post on here and sadly it's about my 5th gen tranny plague

I've been driving my car (99 Base Auto) for a few months and everything was great when I bought it. Then I had a major oil leak (Rear main seal, crank seal, and valve cover gasket) I got that fixed. Another few months and now my tranny is going on me. Started to slip gears, and then now it won't go into reverse, and when it did, I couldn't drive past second gear. I'd be going 30mph at 4000rpm. I was REALLY low on ATF so I went to carquest and got some Honda ATF put about 2.5qts in hoping that'd just be the trick I needed, but I guess not. The car is at 159,xxx miles should I fix it or just get a new car?
This is a picture of when I first got it.