I am going to speak from the heart here a bit...
It was my dream to play a D1 volleyball, ever since I was 14. It consumed me. In my freshman year in college, I failed walking on at a really good D1 school. I really wasn't close both the physical sense and in terms of skills. I worked really hard the remainder of my freshmen year. The coach was pretty cool and let me spend as much time as I could playing with the red-shirts he was ignoring. Sometimes the alumni would come out and play with the red shirts. I ran across some pretty good players. I also found other games wherever I could. My sophomore year, I transferred to a JC and had really a pretty good year. I got a lot better. So much better that I got invited to walk on to a D1 team. The program at the second school was not considered very good at the time. My chances were decent not only at making the team but getting some playing time. Unfortunately, I ran into some physical problems (I only really understood them 15 years later...). I wasn't getting it done, and they cut me after four months in the program, the final round of cuts. I was absolutely gutted. I pretty much checked out of life. It took me almost a year to get going again. It was as if who I was, was suddenly gone, an identity crisis of personal proportions. Toughest time of my life. Without the support of family and friends, I can't tell you where I would be today.
I don't know anyone who wanted it more. I worked harder than 98% of the guys in D1 programs. Maybe, I could have worked smarter. But honestly, I just did not have the combination of physical ability and skill to make it. But (and huge but) I have the satisfaction of knowing that I did everything that I could and that I gave it my all. I don't have any Uncle Rico moments... ha, ha!
Based on my experience, I'd advise you to stay in the D1 program you are already in. I gave a lot to be where you are right now only to fail. There is a notion that the grass is greener on the other side. I'd advise you to be content where you are, get a great education, and set a foundation where you can afford to play golf for the rest of your working life.
If you do decide to go for it...
Worst case scenario, you'll get a lot better at a game you can enjoy for a really long time. It certainly sounds like you have the physical ability. It just seems to me though that you need more time. Golf is a game of moderate physical ability and a ridiculous, ridiculous, amount of skill. Frankly, it takes a lot of time to develop those skills, more time, I think, than you have to jump into the D1 level next year. If it is your dream and it's what you really want, I'd advise to take a year off of school, consider it a red-shirt. Put in eight to ten hours a day, every day. Get a good swing coach and a membership at a club. Work on your swing until you are hitting fairways and greens, consistently, round after round after round. Work on the short game so you can recover when you don't hit greens. Play in as many tournaments as you can to get playing experience. Get into a JC program the following year, see what you can get going. Take it from there.
I will relate one example (hopefully this will give you some hope). When I was at the JC, there was a dude (great guy, BTW), basketball player, that had played only two years of volleyball at a high school not known for volleyball. At tryouts, he was pretty bad. It was obvious that he hadn't played much. I didn't think the coaches would keep him. Here is the kicker, physically, he was a monster, 6-6/6-7, jumped out of the gym, could dunk a basketball pretty much however he wanted, etc... I am guessing he could touch north of 11'8", probably more like 12' later on. The coaches kept him on the team as a red shirt and paid very little attention to him. That got to him. He spent the summer and fall doing nothing but playing, playing, playing, training, training, training. By the spring of his sophomore (red-shirt freshmen) year he dominated California JC volleyball. Hands down, the best player. He followed up the next year with much more of the same, went on the play D1 and earned all-American honors. He even had a stint playing professionally in Europe.
Granted, golf is a different game. The physical advantage that my buddy had in volleyball doesn't apply hardly at all in golf. But, you will never know unless you try. The great thing about life is that you write the script. If it is truly your dream, go for it. Just have the sense to come up with a realistic strategy to get there and be honest with yourself and where you are right now, and how quickly you can get to where you want to be. Use your eligibility wisely. Get as much support from family as you can. If you have the talent and you are willing to work, you never know. Work hard, but first and foremost work smart. Time is your biggest enemy, you don't have any to waste.
Your story about volleyball hits home since it is quite similar to mine in lacrosse, I worked extremely hard, harder than most if not all of my colleagues, but simply didn't see the fruits of my labor. It took a big toll considering I have been playing and working hard since I was 14 as well. I know the feeling you're talking of and it made me realize that sometimes you just have to cut your losses and move on.
Reading all the comments on here made me realize I don't have the means to pursue this with a high rate of success, mostly from a financial standpoint. There's also no way my parents would ever support me dropping school to do this. My priority number 1 is still school but my time outside will be spent on the course.
Regardless, my new fascination in golf has helped me take my mind off of things. I've already seen progress from the practice I've been doing lately (just the other day I shot in the 80s again, without using a driver or fairway wood ) and am going to do my best to get a job at a golf course whether it be a public one or a private club to continue practicing smart. At least I will be spending my time doing something I really enjoy and maybe working somewhere I enjoy. I also know I won't be let down if it doesn't work out because unlike lacrosse, progress can be tracked much more precisely.
Walking on a college team is really tough unless you are playing pretty good. I would have to agree with all of the other comments saying that if you are a 20 handicap, there is probably no chance of walking on to the team, especially D1. As some of the other folks had mentioned, there are more recreational club teams at colleges these days.
Being a varsity player for 2 years of school and not playing on the varsity for 2 year, I can say college is a lot more fun if you are not playing a collegiate sport. The time and effort of a varsity team is huge. Stick to the club team and get out there to play more and have more fun.
I wish there was a club or intramural team but there isn't any I know of. If the 'fun' you speak of is partying, well I've been there and done that. At this point I'd much rather wake up early on Saturday morning to hit the links than nurse a hangover.
Thanks again for the comments everyone