In relationships, it's very crucial you give people space(when they're busy, tired, etc). However, don't invest yourself and your emotions in someone who sees you/spends time with you ONLY WHEN THEY HAVE THE TIME. It's a red flag! Actually, apart from occasional or very pressing moments, the fact that someone is tired shouldn't necessarily stop them from seeing you if the person really likes you. If someone loves you, seeing you/spending time with you actually invigorates and rejuvenates them when they are tired. Don't feed someone with yourself who shows repeated signs of LACK OF HUNGER FOR YOU! "Don't waste your time with someone who is not willing to waste their time with you!"