Thank you for contacting JustAnswer.
I am sorry to hear about the problems you are experiencing in your relationship. Remember that love is a verb. Simply telling someone you love them is not love; it requires acting in a consistently loving way. You may want to ask yourself whether this man is acting in a loving way to you. If not, then remind yourself that you deserve to be loved and treated with respect. Start by treating yourself this way.
Lies and denial are definitely signs of problems. Marital therapy may be helpful at this point to evaluate whether there are ways to improve the relationship.
One thing I would add is that it seems that you have been doing quite a bit of emotional work about this relationship. In order for this to be a healthy relationship, we would expect your partner to do a relatively equal amount of emotional work (if you balance it out over time). This may be one way to evaluate if someone is committed to a relationship and to changing in order to make the relationship work. You deserve someone who will put the work into the relationship as well, since it takes two people to make it work. Also, I definitely believe in trusting your gut. It is often a very good indicator of red flags that should not be ignored. Feelings of love tend to be very irrational, while the gut is a good barometer of danger, both physical and emotional. I hope this answer is helpful. Please let me know if I can clarify further.