My horse is learning fast and doing well, but she is young and does have the issue of resistance to the bit. The problem with her is not that she is always resistant, but that we want her to become more consistently willing to get on the bit (we're doing basic dressage, and she just got under saddle again after ~3 months off due to arthritis). I also don't ride my horse every day.
I'm not sure what discipline you are doing, but using side reins and lunging has worked wonders for me. I warm her up with side reins, and they are gradually getting more tight, so she is getting on the bit working against her own pressure rather than mine (or whoever is riding). I do 10 minutes of lunging before every ride (5 minutes each way -- since it's somewhat of a tight circle, best not to do too much, even if the circle is actually pretty big like mine). The side reins are very helpful!
Next, I honestly do not have the experience to handle my issue so I'm working with a professional trainer who rides my horse twice a week. I know this can be pricey, I'm not sure what your budget is or your experience level, but if you're having trouble you should try to have a professional ride your horse even once to see if they suspect anything more than a behavorial issue (maybe a health issue) and they can give you some pointers.
A lot of this issue stems from the problem with going forward. Horses need to determine the "forward factor" which can be taught using lunging, but you need to determine it in the saddle. If you need more clarification, I would suggest starting another thread because that is a very elaborate topic with a lot to say.
You might have already known some of this, so sorry if I was repeating things! Happy easter and I hope some of this helps :)