Perhaps the gap between the sins is actually made longer, which is a sign of improvement. But the day you think you’re not clean enough to pray to Allah is the day the devil, Shaitan, has convinced you that you’re not even worth it. That was his plan.
Don’t allow that day to come. Remember to turn to Allah. Don’t give up. Never give up. You navigate through your difficulties just like we all do. They may be bigger, but Allah has given you the strength to go through it.