There is something called "selective memory" whereby people remember what they want to. It's possible your T has issues dealing with your affection for him and rather than "remember" you have feelings for him, it's easier for him to forget it. Don't let his "forgetfulness" cause you to question what you believe to be true. You are not "going mad". You know what you've been telling him for months. Stand by your belief and, if need be, give him some slack. Remind him of what you've said. See how he responds. If he tries to change the subject or redirect the conversation then you know he has trouble dealing with this himself. You may need to speak to another T to get help. Don't let your T's lack of memory confuse you or throw you off balance. Have confidence in yourself.

PS: When people say they saw you at the beach, most likely, their view was from a distance. There are probably a zillion people that look like you from a distance.